I can appreciate having a car can be useful, but I'd not call it a necessity. Perhaps things are different in the US of A. The perceived poverty threshold is a lot higher. In many countries, if you have clothes, a roof over your head, and can eat regularly, you're good.

American urban planning is heavily car-centric. They talk about "walkable communities", because the opposite is the norm. A large proportion of American towns and suburbs are sprawling, low-density and strictly segregated between residential and commercial developments. Public transport is often meagre or nonexistent. Parts of America are practically uninhabitable without a car. It's probably true to say that Americans are unreasonably attached to driving and averse to walking, but at this stage it's a self-perpetuating cycle.