The connection between the solar panels and the charging station is fairly incidental, they are both grid connected. It really doesn’t matter much if the cells are over the parking lot or half a mile up the road, but parking lots are often under utilized area in densely populated areas so it can make sense.
As for solar cells I’m cautiously positive. A quick glance at google tells me the EROI is fairly good, so unless they deplete limited resources I don’t see why we shouldn’t use them. But they cannot be the primary energy source, all grids need reliable sources to provide base load power.