Why wouldn't there just be on-demand car rentals? Wanna go to the movie? Request a car 5 minutes in advance and the nearest ones with capacity for your passengers show up. Let the car go right after you get to the theater and make another rental call afterwards. Far fewer cars will be in much more use.
Sure there'll be some negative aspects to just renting on demand, but it'll probably be a lot less than the negative aspects of everyone owning a car.
The biggest net negative is the continual replacement of labor with capital, putting more power into the hands of a few.
Think carefully- what about your described usage is truly distinct from what ZipCar offers? What significant value-add would an autonomous car provide?
I argue that ZipCar is already a perfect model of what it would be like, because ZipCar already does what you describe.
* The car would come to you
* An area that has heavy usage could see cars called in from lower utilization areas
* I don't really enjoy driving
* Ride sharing could reduce customer cost.
I mean, seriously, if busses would just show up when I was ready to leave and went pretty much where I want with only a few stops, I'd just ride busses all the time.
So, this request a car and it shows up 5 minutes later only works in the densest urban areas. In less dense cities and suburban areas, I don't see how there's any chance. Try ordering a taxi from the suburbs, see how long it takes to show up.
Sure there'll be some negative aspects to just renting on demand, but it'll probably be a lot less than the negative aspects of everyone owning a car.
The biggest net negative is the continual replacement of labor with capital, putting more power into the hands of a few.