Cleanliness issues aside... (Score 1)

Ok, for one moment assume people decide to take good care of the cars even though they don't own them, and that some sort of cleaning and maintence routine is figured out. Now, all of this aside, what is one of the most annoying things about vending machine systems? They run out! How much would you rely on a system that depends on the ratio between incoming and outgoing traffic to get you where you need to go? I can just see the bussiness men and students, late to classes and meetings, rushing up, only to find that someone else has taken the last car.