Actually, it's more feasible than you might think.

I have a friend in Blacksburg who's lived his whole life without a car (he's about 10 years older than me). He's held a regular job in the entire time (walks to work normally, rides the bus in bad weather). In town he walks where ever he needs to go or takes a bus, and he lives reasonably close to a grocery store. He likes to travel and probably travels more than most people (usually flies or goes by train and knows how to get good deals on his trips).