Yes, most people I know, like us only use their cars because they have to. I commute to work on the train because I can. But the school run is different as this would involve a 1.5 mile walk and two bus changes.
Our car usage has never been dictated by the price of petrol so far, and I can safely state that we use our car responsibly as far back as when petrol was less than £1.50 a gallon (equivalent to around 33p litre).
I think you will find that the price of petrol in the states has rocketed from less then $1 a (US) gallon to nearly $2 a gallon and this has not change the American driving behaviour one bit. This is probably most people use their car for essential trips like to and from work and the weekly shopping. Unlike us, the Americans actually have a very decent school bus systems for most if not all "public" schools.
Who said anything about unlimited use? I don't have unlimited time to drive my car for unlimited miles, and I suspect neither do you!
I am no fool and unlike you I do not wish to pay any more taxes so that the government can squander it on useless computer systems, useless domes and a health system that does not deliver what I need. But if you feel the need to pay more tax because you wish to fund these useless systems, then please go ahead. A particularly good way to do this is to buy more fags.