En route to completing my first Amazon Go purchase, I tried oh, oh, oh so hard to trip up the watching-me-all-the-time system. I took items out, perused them as if I cared about their ingredients, and put them back. I picked up an item, examined it, then reached deeply into the shelf to get the "fresh" item in the back. I juggled my DSLR camera, my smartphone, and various products. I picked certain stuff up, picked the same thing up again, then went back to put all those multiples back on the shelf. (Update: I went back to Amazon Go a second time while drinking a Coke I'd purchased during my first trip, then picked up and returned the same type of can while sipping on my paid-for drink.)
But really, there wasn't much I could do to mess the system up outside of putting things in the wrong place. Amazon Go, for the most part, is designed to make the process of "oh, I changed my mind" very visually clean. Shelves are stocked with shape and color variety in mind, and they have rigid item-placement spots. Those factors combine to make it very difficult to put stuff where Amazon doesn't want you to. Got the wrong butter? There's only one reasonable place to return the butter of your discontent.
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