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When I started reading the description, I thought: "someone finally delivered on that RFID pitch of just walking out of the store". Was surprised that it's actually computer vision.

Same. I remember predictions of RFID-based shopping becoming the norm 10 years ago, but it never happened. Does anyone know why the tech didn't pan out that way?

RFID tags are still to expensive in the supermarket context. The margins are usually razor thin (at least in Germany) and the products are quite cheap. Even when buying RFID tags in bulk they are too expensive.

I know the standard already exists (It's called EPC), and it is actually used a bit. I recall last time I bought socks at Walmart, there was actually an RFID tag inside the label. I believe they're used a bit more in the supply chain, but AFAIK no retailer actually uses them at the point of sale yet.

One reason I think the retailers took a step back from EPC was the general fear mongering and misinformation. In addition to the crazies calling them out as "the mark of the beast", there were numerous reports in the media about how walmart was going to start "putting computer tracking chips in all the pants they sold so they could track you wherever you went." I'm pretty sure they were also supposed to give you cancer and kill baby seals, too!

Disclaimer: I am more or less pulling this numbers out of thin air.

Assume that having a single cashier costs $15 per hour. Assume that an RFID tag costs $0.05. Assume that in average a cashier handles 1 item for only 5 seconds (including payment).

That means that a cashier can handle 720 items per hour, and that costs the supermarket $15. Having RFID tags for 720 items would cost $36. That's still a ~$20 dollar difference, which still amounts to ~$0.028 per item.

I would be willing to pay that if that means i can forgo the checkout lines.

The problem is RFID, while cheap... is not cheap enough. It's still most economical to keep RFID on the case level.

It's also really easy to take the RFID tag out of a product. Machine vision is likely the cheaper/more secure approach.

This doesn't seem like the kind of store concept where 10c/product would be too expensive.

That sounds about right. Depending on the store, though, the cashier will handle a lot more articles. E.g. at Aldi, a cashier is expected to process at least 3k articles per hour.

The big problem is: Most people are not willing to pay for that :) Depending on the product, 1-2 cents might be your whole margin.

That makes sense. I had assumed that RFID tags were at the sub-penny level of cost by now. Looks like they're well above 5 cents even in bulk.