I'm in a town of around 12,000 people. It's easy to go extremely car light here, but car-free would be a challenge. My day-to-day needs are easy to meet locally, but when I need a bookstore, a bike shop, clothing, a lot of computer supplies or numerous other things I'll need only occasionally, I've got to go out of town. If I lived in the largest city in the region (with around 150,000 people) car-free living would be much easier since it would have everything I need.
I've been in some smaller centres which have become hubs for the surrounding area. In those communities, it's easy to go car-free because all businesses and services are close at hand.