For me, the top two reasons for using a car are distance and cargo.

I can't work from home. My place of work is a 30 minute drive away. I can't afford to live close to work. Biking is second best to a car, but that would quadruple my commute time. I would rather be homeless than spend spend 8 hours working and 4 hours commuting.

Because of sub-urban sprawl, the only way to buy anything locally is to travel at least 10 minutes by car, which would be over an hour roundtrip on a bike. Unfortunately, being homeless wouldn't fix this issue.

I don't live in Seattle or San Francisco, so biking during the summer would be a nightmare, because there are no showers at work. I'm not going to be sweaty and sticky at work for 8 hours. They don't pay me enough for that. Again, I'd rather be homeless.

Whenever I need to move something that can't fit on a bike (e.g. groceries, mattress, desktop + monitor, etc) a car of some sort is the only option.

A third reason is that I want to move out of the city, and a car of some sort is absolutely necessary for that, because of the distances involved. Even if you lived in a small town, you would still need a car to get to visit friends outside of town.

Cars solve real problems that no other alternative can.

The reason driving sucks in cities is because states plan cities in order to maximise tax revenue. If that means you and I have to suffer the whole time, they will watch with glee, like a Goa'uld.