You could also greatly increase parking density in parkcades if all vehicles had autonomous parking. For example, it would be no problem to box cars in if vehicles could move on their own to let them out. I bet you could easily double parking density.
Taken to the limit of the idea, the whole parking structure could be entirely sealed to the outside, and maybe even evacuated or filled with a non-oxygenated medium (e.g. nitrogen) to prevent car fires and reduce rusting from long-term storage. Sort of like a modern grain silo.
I'm somewhat uncomfortable with parking infrastructure that assumes that all the cars are working and "gassed up." If the car boxing mine in is left to sit in the parking garage for a few months (as might happen in, say, an airport's long-term parking lot), its battery will likely go flat and it'll be incapable of getting out of my way.
Even having automatic standardized charger coupling for every parking space wouldn't really work, since the car boxing mine in could have just plain rusted.
Current infrastructure doesn't have this problem: if the car beside mine can't get out of the garage on its own, that's between the garage and a tow truck, but is no problem of mine.