This strikes me as yet another over-engineered workaround for a problem with society. In Japan, I rarely wait in line at a grocery store or convenience store. If I do, it's a short wait, and my interactions with the staff often brighten my day a little bit.<p>Why is Japan different? For one thing, they use a checkout system that is designed to move lines quickly. Two employees can work concurrently, one ringing up a customer and the other handling money exchange with another customer. Customers do their own bagging in a seperate area. The POS system takes cash in and spits out the correct change, and also handles IC cards, credit cards, Apple Pay, etc seamlessly and usually without requiring anything more than a PIN at most. And of course, customers can prepare exact change or get their cards out and place it on the tray while the cashier is still ringing them up. And the final, most important element is the people--polite, attentive, careful, and professional. Cashiers are trained to call out every item and price, and offer extras such as ice packs for cold items, dry ice for ice cream, utensils for ready to eat items, and so on. A quick, efficient, pleasant interaction that ends with a bow and a gracious thank you goes a long way toward encouraging everyone to treat each other well. And, by the way, the money that would be sunk into Amazon's infrastructure and inevitable support services goes to keeping people in jobs.