> And attributing funds to the correct place is the whole reason price-based economy works.

you don't need to know. same logic you're using could be said to justify the current user hostile tracking. the economy existed before analytics, and will continue to exist after it.

if you insisted on knowing, a simple counter will do.

> How do you know whether your blog is generating sales, or whether it’s the Q&A website, or the Youtube tutorials?

Is there no other way to determine that other than feeding traffic to unrelated third parties who build dossiers on everyone?

> How do you know whether your blog is generating sales, or whether it’s the Q&A website, or the Youtube tutorials?

No one is entitled to knowing that information. Certainly not at the cost of our privacy and basic human dignity.

You get explicit informed freely given consent, and then ask people. That's how. You act like not having that information is of paramount importance.

This may or may not be helpful depending on your business/user-base but one option would be to have a different URL for your site that customers can opt-in to beta-test early features, changes, etc... Give them some perk for doing this. Some free thing(s), extra features, etc... On that beta/release-candidate URL require their accounts flagged by the end-user to have double-opted-in to advanced analytics. Some people love to try out new features early. In the event a change breaks something ensure those that opted in can still go back to the main URL of your site.

Tell your legal team you want the opt-in legal language to be easily readable and understandable by the average person and make the font big so nobody can say there was fine print.

Advantages:

- People that opt-in to such things are far less likely to make a stink when something breaks. Again, reward them for finding bugs even if its something trivial. Maybe even set up a private community forum for these people to discuss the bugs they find.

- These people will also go out of their way to find bugs for you. Real-world traffic meets a free Quality Assurance team.

- Your Beta/RC URL can be excluded from any service level agreements in an updated AUP/ToS. Finance people like such risk mitigations.

Disadvantages:

- More work and cost up front to set this all up even if it pays for itself in the long run.

- Requires a bit of humility and discipline to openly share your errors with a handful of your user base.

If you need user information to troubleshoot your site, then you'll need their explicit informed consent. Without it, you simply won't get to troubleshoot and will have to find some other way to fix your site.

You should design your site so that you can troubleshoot it without using real user data. Failing that, you should receive voluntary informed consent from the users, and exclude those that don't consent.

A/B testing / etc is a form of human subject research, the only way to experiment on humans ethically is to have voluntary informed consent. The fact that you're 'merely' running psychological tests on website users instead of performing medical vivisections doesn't free you from the moral and ethical obligation to acquire voluntary informed consent.