The car-centrism of the USA is IMO because people like the convenience of being able to go where they want, when they want, and not waiting for a bus that will take an indirect route and twice the time. People also like living in their own house with a fenced back yard and not having neighbors on the other side of the wall/ceiling/floor. This means we're more spread out (we have lots of land) and mass transit is less practical.

In dense urban areas we do have good mass transit and it's relatively more common for people to not own a car.