Given Amazon's knowledge in warehouse operations and supply chain, I wouldn't guess they plan to use this technology widespread in grocery stores. At that point, they could take a simpler approach than all the cameras and computer vision, by instead treating a grocery store like a warehouse or vending machine (no human shoppers like other grocers today who offer delivery). People enter their orders online, and stop by in person to collect their cart at the front desk. All the food would be behind closed doors. Only downside to that is customers who want to leisure shop and browse for new items.