Granted. However, the problem with public cars is, that because of the societal dictate of a 9-5 workday, everybody needs the car at the same time. Further, because of the layout of the typical city (businesses in the core, residences on the outskirts) the cars would be spending half of their travel time empty. In the morning, they would go to the outskirts, pick up people, and drop them off downtown. Then they would drive empty back out to the outskirts to pick up the next batch of travellers. The reverse would happen during the evening. If we had more homogeneous city layouts, mixing residential and business, commutes would be shorter and public cars more effective. Why, for example, do we not have combined office/residential buildings? It would sure cut a lot of commuting if all a person needed to do to get to work was to take the elevator.