Google engineers joked about how incognito mode isn't incognito
futurism.com
futurism.com
Incognito Mode basically puts you in a mode as if you had installed a fresh, new instance of the browser every time, e.g. none of your past cookies can be accessed by any websites. Websites, though, can still use analytics APIs, including things like Google Analytics, to track you within that Incognito Mode session. They may also be able to correlate you by, for example, matching your IP address. And, to be clear, the Incognito Mode new window has always made this clear.
I can still be really concerned about Google's overall tracking and also point out this lawsuit is a bullshit money grab from lawyers hoping for a lotto payout.
In addition to:
Now you can browse privately, and other people who use this device won’t see your activity. However, downloads, bookmarks and reading list items will be saved.
It also explains:
Your activity might still be visible to:
• Websites you visit
• Your employer or school
• Your internet service provider
As a totally non-web example of this, as of 2017, "Google’s third-party partnerships ... capture approximately 70% of credit and debit card transactions in the United States." https://adwords.googleblog.com/2017/05/powering-ads-and-anal...
When you buy something with MasterCard, in person, with a magstripe or even an old-school carbon-copy imprinter, MasterCard can go give that data to Google.
I think the incognito warning could say "Websites you visit, and anyone those sites share data with" to draw attention to this, but I'm not sure if that's quite enough. I'm leaning towards the argument from this article that "incognito" itself is simply a poor name.
Google's TOS (as you can see linked there) seems to apply to both Chrome and Google Analytics. By downloading Chrome and agreeing with their EULA, you already acknowledge that this data is being collected. I don't really get what people are objecting to, here.
I don't see the difference between that and, say, Coke selling a product called "Diet Coke" that just has regular coke in it. A disclaimer reading "Warning: this is just regular coke," might make it legal but it's still messed up, and I wouldn't blame someone for trying their luck in the courts over it.
And Google's Privacy Policy linked to off of there is one of the subjects of the lawsuit and that it is deceptive.
That's something which should be adequately disclosed by the websites you're visiting, which the problem that GDPR tries to solve (and currently fails to solve due to poor guidance and enforcement). Ideally a GDPR "cookie banner" should simply say "This site uses Google Analytics, <other services> to track you across the web. [Allow] [Deny]" instead of the current dark patterns.
There is ONE simple answer here that is in the best interest of your user, and that's rip the invasive 3rd party analytics out of your website.
Anything else is failing to put your users first, and eventually those users will go to a competitor who does. There's so much opportunity out there right now for startups that prioritize decency.
That's kind of the point of GDPR. But they're not enforcing the main requirements under the law - that the consequences are clear and that choosing to allow or disallow are equally as simple.
> alleges the Silicon Valley giant misled the public about how much data it collects from users even when they're in its Chrome browser's "Incognito" private browsing mode.
The accusation is that Google is leveraging Chrome to track you even in incognito mode, and it does not give any notice that it is doing so. It warns about the websites you visit, about who owns your local network, and about the ISP, it doesn't warn that Google is still actively tracking you in incognito.
- Google Chrome won't track you in Incognito mode.
- Google Analytics javascript (if added by the webmaster to their site) will track you in any mode.
So the lawsuit is saying, "Google promised us that Incognito would let us browse privately, but Google is still tracking us". To me, they're really muddying the waters here, because clientside Chrome doesn't track you, but, doubleclick on a website, will still track you.
According to this lawsuit, Google's biggest sin is saying "Now you can browse privately..." but when you open Chrome Incognito it clearly says "Your activity might still be visible to websites/employer/ISP"
Kind of a weak case for the plaintiff, and a weak article (engineers joked about the icon? and wanted to change the name? It's definitely a shitty name but this article makes it sound like this a smoking gun.)
> Plaintiffs allege that Google collects data from them while they are in private browsing mode "through means that include Google Analytics, Google ‘fingerprinting’ techniques, concurrent Google applications and processes on a consumer's device, and Google's Ad Manager." Id. ¶ 8. According to Plaintiffs, "[m]ore than 70% of all online publishers (websites) use one or more of these Google services."
> Specifically, Plaintiffs allege that, whenever a user, including a user in private browsing mode, visits a website that is running Google Analytics or Google Ad Manager, "Google's software scripts on the website surreptitiously direct the user's browser to send a secret, separate message to Google's servers in California." Id. ¶ 63. This message includes six elements, each of which is discussed below.
[...followed by a lot of detail on what gets tracked...]
https://casetext.com/case/brown-v-google-llc
So there is client-side telemetry which completely de-anonymizes and geolocates you and Google tracks you in incognito mode everywhere that Google Analytics is deployed (~70% of the web). If you use incognito mode and visit porn sites that use Google Analytics, then Google has your complete de-anonymized porn surfing history in their databases. This is not what people are led to believe is happening by the incognito warning message.
This is not supported by the quote you posted.
So not using Chrome. They’re arguing that Google is collecting the usual web tracking and that other Google apps a user might have collect user data.
Why the hell wouldn't anyone? I mean, expectations of privacy have eroded, but "you used this company's product, so you must be giving them permission to see everything you do with it" is an argument that, despite many companies' attempts to push it as just common sense, doesn't and shouldn't fly.
VSCode collects telemetry these days.
I completely agree that it is the status quo, but it shouldn't be. It's unreasonably for people to be surprised by violations of privacy, but I don't think that it's unreasonable for people to expect respect for their privacy.
In that context, companies do their best to guess what their users want and ask for explicit consent when they can't. In Google's case, once we actually dig down and unravel the complaint that was filed by the Texas AG (https://www.texasattorneygeneral.gov/sites/default/files/ima..., page 55-ish), the claim is Incognito mode doesn't stop targeted advertising based on browsing behavior because the fact that browsing occurred is known by the servers. Well, duh. Of course servers have a history of access to them; expecting them to not is like expecting Amazon to not have a list of people that ordered from it (how are they supposed to ship you what you ordered if they don't know that?).
And in the cases where people have gotten retargeted ads because they went incognito and then logged into Google... how the heck do they figure they're in any sensible way "incognito" when their name and face are at the top of the page they're viewing?
Cloud Word and Cloud Excel obviously do, but "online services are online" had better not be surprising.
> Your activity might still be visible to: > Websites you visit > Your employer or school > Your internet service provider
It's pretty obvious that the only thing it's promising is to hide information from other users on the same device, and it goes out of its way to state that it won't protect against other tracking.
Websites mediate a significant part of how a significant chunk of the people in the world live a significant part of their lives. You and I know what incognito mode is and isn't, but can you seriously claim that, among a significant chunk of the population of the world, no reasonable person overestimates the privacy incognito mode offers?
The standard is would a reasonable person and the answer is absolutely not. Among non techies people assume that Incognito/Private Browsing provides less protection than is actually offered. You go into private browsing when you don’t what sites you visit to show up in your browser history, that’s it.
> The standard is would a reasonable person and the answer is absolutely not. Among non techies people assume that Incognito/Private Browsing provides less protection than is actually offered. You go into private browsing when you don’t what sites you visit to show up in your browser history, that’s it.
You quote my referring to what a reasonable person would do, and then seem to be offering a rebuttal by saying that it's about what a reasonable person would do …? Anyway, I think we must just disagree on a reasonable person's expectations.
Yes. What's confusing about that?
They didn't say it was wrong to talk about a reasonable person, or anything like that.
But you were applying the reasonable person test incorrectly. You don't make a pile of reasonable people, and then check if any of them are confused. You look at what a single median reasonable person would think, basically.
I think it’s just fine and I don’t think Google misrepresented anything. But certainly there’s an enormous amount of people out there who still don’t understand the actual implications of what incognito mode means.
I think we're on the same ballpark as calling lane-assist Autopilot.
Those who know, know. Those who don't, don't.
I mean "RTFA" arose for a reason, right?
Stuff literally needs to be "what it says on the tin"... and even then.
Is aviation autopilot really any different than lane-assist?
A pilot under Autopilot is at least allowed to take their hands off off the wheel/yoke/control-stick during cruise-control elements of the flight ...
However, the connotations associated with "Autopilot" (to the wider public) mean it was a terrible term for its intended use on the road.
Maybe this issue is so well known now (I assume, in my bubble thinking) that it's no longer an issue ... but it is a relevant example.
Your activity might still be visible to:
* Websites that you visit
* Your employer or school
* Your Internet service provider
In addition, Chrome is distributed by Google itself and they clearly advertise it as made by them, better and safe. They make it explicit that it is entirely under their control. So, it would be logic for a standard non tech user to expect that google do not track them when they are using the "google" chrome incognito mode.
Keep in mind that a lot of users would not know the difference between a client and a server.
Also, remember that google do everything to blur the lines when it was convenient for them:
When you are logged in Google, your own browser is logged with a special profile icon. If you look at it you can launch a Google search directly from the url bar or from the "new tab" page.
Even as a power user, can you easily reply to the following question? is the new tab your browser domain or Google domain? Hint: some content here is dynamic depending on your Google account...
The incognito default tab says that your activities are still visible websites. The incognito mode even explains that other people using the same device won't see what you browsed - which is the primary use of it anyway. I don't know what is the concern here - are people angry that a mode which doesn't promise untrackability doesn't give untrackability?
> If you look at it you can launch a Google search directly from the url bar or from the "new tab" page.
What is this meant to to poke at? You can change what the search bar does to another search engine (in fact I believe Duckduckgo is also one of the choices in a new install of chrome).
> When you are logged in Google, your own browser is logged with a special profile icon.
Doesn't Firefox also have the same browser sync service? It's a useful feature to track your browser tabs unless you're security conscious or paranoid (or both).
There's a difference between _not_ understanding what a browser does and misinterpreting what it does, which is what this entire post is.
But the spy icon and the name hint something different. I mean we technical folks do understand the words and explanations with one short glance, because we know a browser cannot make us anonymous nor invisible just like that.
But common folks who understand computers as dark magic not so much.
So it is somewhat missleading, even though I do not see a evil intention here, rather misscommunication.
And, to be clear, the whole focus of this lawsuit is the plaintiffs are saying that since Google also owns server-side Google Analytics, that incognito mode is inaccurate because "Google is still tracking you".
But the only way for Google to handle that would be if (a) Incognito mode specifically handled GA differently, and that would be a privacy violation, or (b) GA detects you're in Incognito and stops tracking, but all the browser vendors have gone to great lengths to try to make private modes as "unsniffable" as possible, and I view the very effort to sniff for privacy mode as a violation.
Well, "private" is clearly different from "incognito". But the mask with firefox is misleading, too.
And the article is misleading as well, because it implies that chrome is still tracking you in incognito mode, which is not right. Google might be tracking you.
But to comment on the lawsuit, I lack details.
Well, that’s kind of what breaks intuition about it. Compare to a burner phone. People expect that eg calling the same place with the same number will tip off the recipient that you’re the same person.
But what if every business fed a voice analysis profile of everyone caller to a central database — without keeping a voice recording, of course — and associated each one with a number. And imagine it was cheap for some people to access this database.
That would kind of break most people’s expectations of a burner phone. But that’s basically what websites can do.
So even if you know the general structure of how websites and Incognito work, you might still fail to appreciate how unhelpful the anonymization is.
I find it odd that everyone seems to be just ignoring that the word "incognito" literally means "with one's true identity concealed". It is, in fact, reasonable for naive users to expect that their identity would be concealed while using "incognito mode", Google's disclaimers to the contrary notwithstanding.
"What? Everyone should have known that we didn't literally mean 'incognito'!"
Luckily, every company's engineers can be counted on to point out the irony of the company's marketing bullshit.
The only thing they would learn about you would be characteristics like height/weight/voice/tattoos etc - your IP address - and could use it to correlate you if seeing you in the future
Bear in mind, lane-assist and even cruise control could also be called "autopilots" by this same reasoning. Autopilots in aviation vary wildly in capabilities, and the term is used pretty broadly to refer to any automated system that controls some aspect of the flight, since even flying straight and level at a fixed altitude is a pretty demanding job over hours.
As you alluded to, though, autopilots (in planes) don't generally have to worry about traffic or running into obstacles. The first line of defense is ATC scheduling planes so they won't collide, and in large commercial planes, TCAS transponders that signal the pilot (with a loud aural warning) of traffic that might be a threat, and providing guidance to avoid collisions. For alert pilots, there is usually a lot more time to react to these threats than in cars with only 10s of meters of separation. Some autopilots integrate with TCAS to perform automated avoidance maneuvers, though it's not clear to me how common these are.
At any rate, most people know nothing about aviation, and it's either ignorant or deceptive to call it "autopilot" when the average person thinks that implies fully automated as opposed to partially automated piloting. Driving-assist in this case is automatic and a pilot, but not fully automatic. And when you need response times in seconds to subseconds, you can't afford to "zone out" to the extent an aviation pilot might.
If I then go into a store and say "hey I'm Pat, account number 314b" that's on me. I'm no longer incognito to them. If someone watches incognito me coming out of my front door and getting into my car, they may (reasonably) assume that it's me. This doesn't mean my identity isn't concealed.
I see this disclaimer every time I launch incognito mode. Does it not count?
https://support.google.com/chrome/a/thread/143076679/proxy-s...
The extension makes it possible to use a SOCKS5 proxy (ideally tunneled over WireGuard) for incognito tabs, without affecting normal tabs: https://github.com/pmarks-net/incognito-proxy
https://github.com/jameswmccarty/aws-socks5-proxy
...since I'm already using an EC2 instance for my own personal stuff.
(I'm curious because these are the only practical possibilities which come to mind, feels like I must be missing something)
Edit: To hopefully clarify a bit, I think this sounds cool and all, and it's dumb Google classified and shutdown this need as #wontfix.
I fully accept the shortcoming in understanding the legitimate use cases is completely on my end :). Genuine curiosity, not trying to rain on you in any way, @p1mrx.
Privacy and peace of mind are goals on themselves
And does "nothing" to stop ISPs or websites tracking you.
Not sure how anyone can misunderstanding what data is or is not saved when it's stated on every new incognito tab.
How is "not understanding plain English" a valid counter argument? Here are the specific words to which I believe you are referring-
> Your activity isn’t hidden from websites you visit, your employer or school, or your internet service provider.
The issue is websites still collect data. Like the website knows your ip address, your time zone, and the website can fingerprint to some extent. That includes Google.com, not via Chrome when in incognito mode, but via the fact that you access Google's websites.
They don't know it's you directly.
All that incognito mode does is delete those session cookies when you close that tab or window.[1] If you want to avoid being tracked, turn off cookies altogether (or use a plugin that blocks trackers), turn off JavaScript (or use a noscript plugin), and use a VPN.
This site gives you the details: https://amiunique.org/fp
Basically unless you use a completely different computer for incognito browsing, any site you visit can link your logged-in identity to your browser fingerprint and then track you regardless of mode/cookies.
It's likely only things like referrer and device groupIDs which are easily excluded if the goal is to track a user across browser modes.
The issue is that incognito mode is only for the browser itself - they can’t force the sites/services you use while in incognito mode to change what they do.
<https://www.bloomberg.com/news/articles/2022-10-11/google-s-...> Paywall / regwall: <https://archive.ph/jJQfq>
In the event of an acquisition a consumer should have complete legal authority to decide whether there information transfers to the new company, and it is opt-in only by default.
How would you sensibly have this work with a publicly traded company? Or any corporation, really. Every time any stock changes have all the data they have is unusable?
If data is shared, for any reason outside of the boundary of the legal entity, or if the legal entity is absorbed by another one then data can only be transferred with the consumer's permission.
https://support.google.com/chrome/answer/6130773
Some OSes, MacOS for instance, also have a guest mode for the entire OS. By default it only allows Safari but you can add other apps. Also by default it deletes everything when you log out of guest mode.
https://support.apple.com/guide/mac-help/set-up-other-users-...
This would at least create an interesting incentive to split apart businesses and keep them competitive rather than consolidating.
"Guest Mode": (1) hides the identity on the internet, and (2) hides the activity on the local machine.
"Incognito window": (2 only) hides the activity on the local machine.
To clear the confusion, "Incognito mode" should simply be renamed "Ephemeral mode" or "Transient mode" or "No-Save mode".
I definitely don't use it just to keep a site from appearing in my browser history.
Firefox, although having a questionable owner, is pretty great for privacy.
Brave, is coming along in leaps and bounds for good out of the box privacy.
Even Microsoft Edge seems to better at privacy than Chrome at this point..
Has Chrome become the new Internet Explorer?
I'm wondering how much more discovery material there will be due to the widespread transition to work from home.
To be clear I don’t think this lawsuit has much merit. But the marketer’s concerns are valid.
I searched around, but Google's explanation isn't transparent and the stackexchange post didn't reveal anything of consequence.
it may make sense to compare incognito browsing to someone with memory loss. you will forget that you talked to me, but i'll still remember (your ip address and your browser fingerprint, and that fingerprint may be enough to link your incognito tab to your other tabs and to your actual identity).
Google websites don’t know whether they’re being visited from an incognito tab or not, and Chromium works hard to ensure they can’t know (because knowing a user is in incognito mode is itself a privacy leak), so they track anything they could otherwise track without the logins and cookies which are excluded from the incognito sandbox.
But if you go to a website, like nytimes.com, it knows your ip address, etc... that's also true of google.com, and ads served by google on nytimes.com
- Brave
Obviously anything within an incognito mode session will be trackable within that session, but Google is not linking it to anything not provided within the session.
Anyway.
As a former Googler, I'll say this: You will have a hard time finding people more critical of many of the actions of Google (the company) than Googlers (the employees of said company.) Even after all these years, and into the Sundar times, there's a rather healthy internal culture of critique there. Usually with the best interests of the broader mission statement of the company at heart.
Naturally much of this is necessarily muted in external communications, and in some forms of writing... for legal reasons. Sounds like some people slipped up here and didn't pay attention in their mandatory communications training.
TLDR it's not "damning" -- geeks inside Google are much the same as geeks outside. They're just taking a paycheck.
More critical than people who wouldn't even take a job at Google for ethical reasons? C'mon..
> Sounds like some people slipped up here and didn't pay attention in their mandatory communications training.
"You can say whatever you like inside the company, but never talk about it outside"
So logically there's a dude who sits in between the raging unwashed and my pure genius whose job it is to transform my pearls of Platonic percipience into something consumable by the gut flora of the lay people.
This is necessary because the lay people are ever so eager to find witches and burn them - this act mostly out of sheer pleasure than self-defence.
Arguably, if you did pay attention to said training, and deliverately sought to not call a spade a spade you are part of the problem.
If legal tells you to call something something else, that's when you need to start getting suspicious.
I think it's good to have a critical culture of our own products - otherwise we would have blind spots!
That's a huge difference. Between people willing to take blood money and those not.
This is plain apologism.
Solutions to systematic problems require a systematic approach. Personal blame solves nothing. I chose to leave Google, and I took a huge financial hit for it... but I wouldn't reproach anybody for staying there, especially around here where the other employment options aren't so great.
"Your activity might still be visible to:
Websites that you visit
Your employer or school
Your Internet service provider"
The sentence you cite suggests that it's "just" such sites that see your activity, while it's a third party (Google) that does as well and that is the issue here.
Sure, technically you could argue that the tracking is "part" of the website that you visit, so it's technically still "only" the site that's tracking you. But let's be honest here, no reasonable non-hair-splitting non-geek would read it that way.
Is there other ways Google is tracking you in incognito mode? Additionally, there's other websites like Meta or things like Fullstory, segment, or really any third party tracking that gathers data in the same way GA does.
Right, so only just about every website on the planet.
> In either case, it's explicit in how Google gets your information.
It's not explicit at all. The vast majority of users would not understand that's happening when they're in incognito mode.
https://support.mozilla.org/en-US/kb/common-myths-about-priv...
> Myth 1: Private Browsing makes you anonymous on the Internet
> Reality: Private Browsing does not mask your identity or activity online.
On Mobile Safari I use private browsing for my kid's youtube, so my recommendations aren't full of minecraft videos. But now that I think of it, it might be fun to teach youtube that people who watch minecraft videos are also interested in type theory and Edward Kmett videos.
#notallspouses!
It's for being able to open a tab while screen-sharing with strangers (colleagues, friends) without the browser suggesting porn sites with matching keywords.
That warning doesn't include Google tracking you as well.
Nothing wrong in making world a worse place if you’re being paid for it, right?
I suppose a corporation is not a democracy but a private entity, so then, what are the employees? free citizens? who has more power the government -- which was supposed to guarantee that the citizen's voices would be heard, or the company?
how different is google from the usa government really?
Without pretending to know enough about the circumstances of any individual person, I hope you can come to see how this description encompasses both "bad" and "good" (or at least "excusable") conduct.
There is some line, which is difficult to see and controversial, where one can no longer justify their work by saying they are just a cog in a machine. We can talk about that line and that line is clearly different for different people (do they need the money, do they support others, how easily could they leave, etc).
Asking people to account for the machine they are working for is a fair and normal social act and we should all be reflecting on it.
OK but Chrome explicitly states that it only protects against other users on the device seeing your history. It also clearly states that other entities may be able to see the history. So if you thought the purpose was "preventing others" in a general sense, that's on you.
They state that Google attempts to collect information on you even when in Private Browsing. Yes, no shit, all websites will work exactly the same way via Private Browsing. All tracking techniques will work exactly the same way. To not do this would mean that a browser would have to tell websites "I'm in private browsing mode", which would be a terrible idea and is just a shittier version of Do Not Track.
OK, so then they talk about "Duplicate GET Requests".
> Plaintiffs allege that Google collects duplicate GET requests.
> ccordingly, when Google obtains a duplicate GET request, the duplicate GET request "enables Google to learn exactly what content the user's browsing software was asking the website to display."
I have no idea what they're referring to. The closest thing I can think of is Safe Browsing, maybe that new off-by-default advanced safebrowsing thing?
Oh, ok, reading on they're... just talking about tracking that websites do. So if Google's JS is loaded into a webpage it apparently will send dupes of GET requests. I'd like a source but they only talk about how Facebook does this...
> Second, Plaintiffs allege that Google collects the IP address of the user's connection to the Internet, which is unique to the user's device.
Yes, websites can see your IP address... also websites have been explicitly called out in the private browsing page as still being able to track you.
> In addition, Plaintiffs allege that, for users using Chrome without Incognito Mode, Chrome constantly transmits "a unique digital string of characters called Google's ‘X-Client-Data Header,’ such that Google uniquely identifies the device and user thereafter." Id. ¶ 95. However, Plaintiffs allege that the X-Client Data Header is not present when a Chrome user has enabled Incognito Mode. Id. ¶ 96. Accordingly, Plaintiffs allege that Google is able to tell when a Chrome user has enabled Incognito Mode. Id.
Yes, this is an example of Google not sending data to Google during private browsing.
I dislike this header, personally. I believe that Google should remove `doubleclick` from one of the sites that it will be sent to, but I don't think it's relevant to this case. It is so far the most relevant thing though.
I also believe Google should not send the tracker to "youtubekids.com" and that may actually be illegal in the EU, possibly even the US.
And that's it. So, most of this is absolute nonsense, and there is one issue that I think Google should address but it's not related to the misrepresentation of Private Browsing at all.
Journalism really is pretty dead these days - tell us something we don’t know
I don't think a new incognito tab warns you about that.
An incognito mode explicitly informs that "Your activity might be visible to website you visit". Unless you are intentionally trying to conflate Google and Chrome as a single entity, it's pretty clear that Google is going to collect some degree of user information. Let's stop being ridiculous here.
The one thing I keep a Chrome browser for is printing, I prefer it over Firefox's.
1) https://blog.mozilla.org/en/products/firefox/firefox-rolls-o...
But there's also container tabs, which fully isolate content and context from one another (though of course IP-based tracking remains effective).
I encourage you to see for yourself how much there is, visit about:config and filter for "telemetry" and then "beacon". It's a lot.
They track things like every time you close and open the browser, check for an update, and lots more. I took an hour to through and disable it all on each of my machines.
Ouch. Someone envious, maybe?
> Now you can browse privately, and other people who use this device won’t see your activity. However, downloads, bookmarks and reading list items will be saved. Learn more
> Your activity might still be visible to: Websites you visit Your employer or school Your internet service provider
'Learn more' takes here:
https://support.google.com/chrome/answer/9845881?visit_id=63...
Nowhere on the tab itself does it say that Google isn't still spying on you. It also doesn't state the opposite, but the starting sentence 'You can browse privately' is disingenuous.
The 'Learn more' link even states:
"Chrome doesn’t tell websites, including Google, when you're browsing privately in Incognito mode."
Which is obviously a blatant lie.
See: https://blog.kagi.com/kagi-features
Been really happy with those capabilities as they really help cut down on my exposure to low quality news/reporting.
https://addons.mozilla.org/en-US/firefox/addon/websites-note...
edit: but it's probably better if you keep your notes in a folder for a single file for each website
It's obvious that "incognito" only disables cookies and other persistent storage content.
To think this anaoymizes your connection is laughable. But for normies I guess that's the problem
e.g. Firefox allows you to restored closed tabs. Chrome does not.
* Don't want companies building a profile on them
* Writing under a pen name and don't want to accidentally link it to real name
* Researching a topic that might result in peers/society judging them badly
* Want to price shop without companies raising prices because of their browsing (I don't think this happens, but it's a common fear/accusation)
* Activists worried about being spied on
* Person with some suspicious looking connections who doesn't want that to reflect onto them (perhaps you have a cousin that joins a enemy of your country - you didn't do anything but just want to email your family about news without getting on a watch list)
* Doing illegal things and don't want to get caught
In fact I'm kind of struggling to think what reason for anonymity is unique to the technically savvy... pirating?