Just over half of Amazon Fresh stores are equipped with Just Walk Out. The technology allows customers to skip checkout altogether by scanning a QR code when they enter the store. Though it seemed completely automated, Just Walk Out relied on more than 1,000 people in India watching and labeling videos to ensure accurate checkouts. The cashiers were simply moved off-site, and they watched you as you shopped.
Grocery stores usually do an insane volume of sales compared to most retail. I’m not sure how big these things were but even if they’re tiny they’re probably selling thousands of units a day. The number of chips they would need and the labor to apply them would almost certainly be unsustainable.