Well, you need a cell phone to even get in, so that would likely have to change too. And then they'd need one of those complicated self-checkout kiosks where you tell how you're paying. Someone would have to deal with all the physical cash (and checks?). And at that point, you're just Walgreens.

I 100% get the logic, but for progress to happen we unfortunately need to break some norms. Like, Uber also requires a phone and doesn't accept cash... if they had to do both of those, they'd just be taxis.