It is amazing to me that
this is the technological solution to eliminating scanning barcodes at check-out lines. The obvious alternative is RFIDs, i.e., just push your cart through a scanner like airport security and all your items appear on the display. (The "automatically bill your Amazon account or credit card" part is optional either way.)
From talking to a couple supply chain people, the best explanation I have heard for why RFIDs aren't ubiquitous, even though they now cost less than a penny (EDIT: I'm wrong, more like 7-15 cents), is that barcodes are too entrenched; RFIDs aren't nearly as useful until everything has one (since if you have to barcode scan half your products, and they are intermixed with with the RFID'd products, you might as well scan them all), and even retailers like Walmart weren't able to pressure all their suppliers to switch at once.
I wonder if this could have been fixed years ago with a collective-action solution like a stronger industry standards body or government regulation.
EDIT: Huh, could have sworn the cheap passive RFIDs cost less than a penny now, but apparently they are still 7-15 cents. That would explain a lot. Presumably the price would fall quite a bit if every product in America had an RFID on it, but we're not there yet.
https://www.rfidjournal.com/faq/show?85