Given property tax rates, charging times have to drop pretty drastically, and they'll need a massive increase in power supply to handle the 15-20 cars supercharging simultaneously.

Gas stations currently make very little to almost nothing actually selling gas (something like 5-25 cents a gallon last I had heard). Almost all of their income is from also acting as a convenience store for snacks and drinks. They need people in and out as quick as possible, not loitering around for half an hour.

Basically, if charging time dropped to the 5 minute range, sure. I would hate to have to use one, though, given how busy gas stations already are during the day around here.