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The print volume matters. These new receipts would be at least 3x longer than they need to be, and thermal paper:

a) costs money

b) is considered to be highly toxic

c) often isn't accepted by local recycling programs (but people still throw receipts in anyway)

d) ultimately end up in the garbage, or even just littering street corners.

More importantly, it doesn't solve the larger problem of "where did my money go?" since that usually is asked over a timeframe of more than one shopping trip. The question is usually "How did I spend $100 more this month on groceries than i budgeted?" and the only way to answer that is analyze all of the spend together

>The print volume matters.

Yes.

There are some good ideas here that would be nice in practice. I like the categories and the fact items within that category are organized by price.

However, IMHO, the bar chart and bubble charts are useless. These will only add to the cost, time, and confusion. Heck, most here don't even understand it.

Where is the cost per lb information (for the meat)? That's useful.

I'm a person who understands things best visually. For me the bubble chart was pointless but the bar chart is very useful.

> b) is considered to be highly toxic

Do you have a source for that? It seems many thermal papers have BPA, but "highly toxic" seems like a bit of a stretch. If you have a study that shows adverse health effects in cashiers (or other populations) who handle these papers frequently, please share it.

edit: Just to clarify, when I think highly toxic, I think of things like Radium Jaw: https://en.wikipedia.org/wiki/Radium_jaw

I'm really no expert on the whole BPA thing, and I've read a lot of mixed research about it. I say "considered" toxic because of some of the research that has come out about it. I think ultimately we're not totally sure of the impact it has on health. There are quite a few studies done on this so far but none are particularly conclusive.

Here's one relating to cashiers: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4824622/

And a more generalized one relating to factory workers who produce products containing BPA (like thermal paper): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5634705/

It seems the government of France is also taking a stance against the use of thermal paper in the EU. There have been some concerns about BPA levels in groundwater, too, but this would be from all sources of BPA that end up in landfills, not just thermal paper.

Calling it "highly" toxic might not be entirely accurate when compared to something like radium, but one of the issues with BPA is we're not entirely sure of the health impacts. As a hormone disruptor, it seems to manifest in undetectable ways (links to heart disease, infertility, etc.) so it may be hard to pin down the effects of exposure until enough historical data has been gathered.

According to Health Canada (my country) 92.7% of their sample population had BPA concentrations in blood, a number that actually increased in the 7 years after it was banned from consumer products. (https://globalnews.ca/news/3694669/bpa-blood-samples-common/)

I'm also not trying to call for an immediate ban on it or anything like that, but merely stating that creating more of it without solving this problem is probably not a great idea.

> The print volume matters.

Someone tell CVS. I don't think I've gotten a receipt from them shorter than a foot in length.

I was going to make the same comment about CVS

That's one of the reasons why I tend to avoid CVS.

For non-Americans, this is not an exaggeration... https://www.vox.com/the-goods/2018/10/10/17956950/why-are-cv...

That article is interesting. It says:

> If you, a non-loyal shopper, mosey into CVS and buy some Tylenol and a package of seasonal candy, you will get a receipt that is unspectacular (read: a normal length).

However, that's never been my experience. If I buy a pack of gum in a CVS, I'll get an insanely long (although not five-feet long) receipt for it even though I certainly am not a member of any CVS affinity program or anything.

> 3x longer

I used to work for a large payment processing company that supplied POS systems to retailers, I was surprised to find that receipt length does matter a lot to some retailers.

The department that shipped till rolls liked long receipts, it made enough of a financial difference to them to matter.

The retailers hated long receipts, because obviously that meant they needed to buy more till rolls.

(It's worth remembering that the customers for most POS solutions are retailers, not the person who buys something in a shop)

I don't think retail customers prefer longer receipts, either.

> I was surprised to find that receipt length does matter a lot to some retailers.

Why did this surprise you? It's what I would have expected.

I also expect that customers like overly long receipts just about as little as retailers.

> The retailers hated long receipts, because obviously that meant they needed to buy more till rolls.

Changing out the printer roll is very annoying as well, for a retailer's cashiers. It's slightly time consuming and it doesn't always go smoothly. It inevitably results in a customer having to wait longer, slowing the checkout process further. The less often that action is needed to be performed, the better.

Receipt printers in the UK universally print at the end of the checkout process. They're very fast - it only takes a few seconds to print a receipt about a foot long. In addition, some supermarkets have a secondary printer which prints colour coupons at the same time at a similar speed. So, I don't think it would be a big slowdown.

> - would waiting to print the receipt at the end cause a big slowdown vs printing as you ring items up? (I believe with most current systems, items can be added and removed, and they show up as 'add' and 'remove' line items, because it does print as you scan.)

Most (all?) stores I go to print the receipt at the end of checkout, and it takes maybe 3 seconds at most, so I don't think that's an issue.

I would also be concerned that the longer receipt length means that people will be less likely to actually read it. (I know I personally tend to gloss over really long/verbose receipts, but I take the time to look at ones that are more densely packed. Maybe that's just me though.)

It takes 3 seconds to print because it doesn’t include any complex rendering (like a dynamic bubble chart) or need full state to determine how to print it. This design challenges a lot of assumptions that the current generation of receipt printers use.

That's the computer's problem, not the printer's. If rendering time really becomes an issue, it can start the rendering process while the humans are twiddling about with card reader terminals and making small talk.

The rendering itself isn't that large of a task and it'd all be done on the POS which has more than enough power to draw a couple circles. There's very little processing done on a thermal printer basically it's just decoding and drawing exactly what the source system tells it to. At most I'd expect it to add a second or two for the POS to do the calculations and send it to the printer.

The print time is proportional to the number of lines with pixels

Watching the fast thermal printers in stores it's fluid enough it might just be directly related to length.

I said this on the other thread but I think the bubble chart should be moved to the back or below. The primary use of a receipt is auditing if they made a mistake and this design makes it harder to do so.

> because it does print as you scan

I'm in the midwest and I've never seen this anywhere

That's the way older cash registers worked. It hasn't been commonplace for a couple decades for big retailers. POS terminals without screens need to let the cashier review mistakes so they can be corrected.

I haven't come across a register that did print as you scan in like a decade now, even in the smallest of stores.

> would waiting to print the receipt at the end cause a big slowdown vs printing as you ring items up? (I believe with most current systems, items can be added and removed, and they show up as 'add' and 'remove' line items, because it does print as you scan.)

print the bubble chart at the end of the receipt, job done