I think it’s because of the way the country was built. Getting from A to B without a car is drastically worse, and it adds up to a proportionally bad quality of living unless you happen to live in a walkable older city (NYC, Boston for example). In some places like Florida your nearest store could be 4 miles away. The bus here is so underutilized and so inconvenient that I don’t think I’ve ever considered. A 30m drive is a 2h bus ride.