I think that’s just because there are more car drivers around. It’s super funny: whenever I’m in the car myself I get annoyed by bikers. When I’m on a bike I don’t understand how dumb some car drivers are. I think it’s just the vehicle you’re in/on which shapes your perspective. Quite telling for other situations too btw
I've thought along the same lines when I go to a busy parking lot. When you're driving, the pedestrians walking everywhere, right in front of you, etc, are very annoying. As soon as you get out of your car and become the pedestrian, you expect the cars to remember that you have right-of-way. Ha!