Hmm.. I suppose technically they can ID your phone via Bluetooth / wifi / However, but that’s too coarse grained. And what if it’s me and you reaching for a tub of butter at the same time? What price is displayed and who gets “tagged” with it? What happens on a typical grocery store shelf where there’s 8000 items within reaching distance? Do all the tags change? lol

Maybe nfc or rfid for more specific detection? But that’s really close … You”d almost have to purposely hold your phone / card next to the tag for that.. and oh by the way, the tag would all of a sudden stop being a dumb eink display with a one-way mechanism, and it would require the ability to do all kinds of fancy radio telemetry not to mention communications.

I feel like if anything were to practically happened it would be closer to the Amazon store concept where they didn’t have any employees and just a bunch of cameras, watching your face and what you picked up and put in your bag or whatever. And then “AI” (offshore people) would charge it accordingly. It would still only work, of course, for use cases were single consumer presence was detected nearby, etc. oh and can you imagine Someone going to a store with a phone zoomed in on the prices recording a video and then watching the prices change as they got closer?

Interesting thought experiment