Not sure if you mean we need cars because we have a small population and long distances of if you mean we have high prices because of small population and smaller customer base. Gas is expensive because we have really high taxes on gas (which I think is great) and public transportations aren't as bad as most people think. The big problem is that people avoid public transportations due to some illogic love of their cars, even when the car costs more and takes almost as long as the best public alternative.