If it becomes popular to share cars then this may work. Looking at reality I have my doubts though. If people wanted to share cars you would see neighbors sharing cars for example. In the US many families or friends not even share cars. When I go out with people it ends up with seven people going in 4 cars or similar.<p>A self driving car takes the pain out of driving so unless society changes a lot we will see more cars driving around (often empty) and people will have longer commutes while sleeping their car.