There are people that don't need a car and can't afford a car.
A lot of these people believe, however, that, as an adult in the US, you HAVE to have a car. They go through great personal sacrifice to keep their cars ("I wish I didn't need to have two jobs.")
If I'm geting this right, they have a certain level of hostility towards those that reject their values. They have not thought out either their "need for a car," nor their hostility to those self-righteous, holier-than-thou bikers, though, and really couldn't articulate mre than they are when they shout.
When I was younger, I kept running inot people at parties who would loudly proclaim, after hearing how I live, "I'd like to be able to do that but you can't live like that."
They always had that second person "you." As though I was talking about some hypothetical person instead of how I really do live.
Most of them did not have circumstances that would make living without a car inconvenient ("I live on a farm outside of McDonald;" "I work a few miles outside of Monroeville;" or "I have 3 kids and two jobs.").
A lot of them were similar to me - they were fit, single, lived on the East End, and worked at a university. Still, they believed "You can't live like that."
Seeing someone who obviously isn't an Oakland-dwelling student on a bike is bound to generate cognitive dissonance for them.
Mick