I'd say way less than half the people I see at gas stations actually go in and buy stuff, the fueling time is the limiting factor the vast majority of the time.

But that's besides the point anyways. Electric cars take forever to charge. So the turnover rate is a fraction of a normal gas station, and thus a lot more stations would have to be built out to accommodate the demand. That's the point, whether or not someone adds an extra minute buying a drink to their quick gas fill up has nothing to do with it