That's likely in the future for me too. However, I mostly supercharge during my travels in Hope, BC, which is a 6 supercharger site, that is halfway between my home and cabin. There's rarely more than one vehicle at that site, and often there's none. I walk a block and a half to the Blue Moose to eat and I don't consider myself as breaching my societal contract if my car fully charges while I'm away since there's no hope in hell someone needs my spot. But I do consider the fact that I hate my car sitting with a full battery so I usually return pretty soon after anyway. I can't see Tesla charging me for failing to return unless there's a need for the space. I wouldn't even consider staying longer than necessary for a charge if there was even a remote chance of keeping someone waiting.