A lot of people are car free because they see the big picture and want to minimize the harm that they do. Unfortunately, a lot of people (most people) in a capitalistic society only consider what they as an individual want. And often, each individual decision, on its own, wouldn't be that big of a deal. One car by itself doesn't do too much damage. But multiply them by hundreds of thousands and you've got carmageddon.

Could every person on the planet have a 4WD for fun and giggles, a car for hauling stuff, a couple of motorcycles, 15 bikes, etc.? No. The planet simply can't support that much fun for everyone. Feel guilty about it or not, that is simply the truth.