Admit it: It’s an enticing thought. A visit to the grocery store completely absent of all the usual irritations: customers clogging the Express Lane with — oops! — at least 40 items. Slow-movers fumbling through self-check-out. Grim cashiers shoving your heaviest items into a single bag that splits open before you reach the car. Amazon has nixed nearly all the pain-points we associate with shopping in a single swoop with the opening of its check-out free convenience store. It might seem like another dreaded retail disruptor. But how can it not inspire a shiver of excitement?