Charging stations don't need all the environmental equipment that gas stations have to catch oil and gas run off. I guess we could convert old gas stations that don’t need extensive environmental cleanup, but building new ones just to charge EVs is huge overkill when you just need some space in a parking lot.
That's a good point. Charging stations benefit from being a service station too though, with amenities and a cafe etc, since people want something to do while they charge. So a gas station is a better candidate than a parking lot when decisions are made for where to place the new charging infrastructure. Lots of other factors too of course.