Here’s my take, this coming from an average fixie rider who is in the military, rides CM,.. but doesn’t really fit into any or even part of said subcultures.

Messengers work hard. Well most of them anyway. They are tight nit, mostly. You are, an outsider. You may have caught someone on a bad day. Some messenger’s may feel that anyone outside of their community is.. an outsider. They may be a bit stand offish. Just as you, or I am when someone we are unfamiliar with attempts to come up and make friends. I’m a bit wary of people naturally, and have to work at being friendly/responsive. I don’t always wave to a fellow cyclist. I’ll stop and help change a tire, been known to interfere in bike vs. car altercations. But generally, it’s me and destination. Is the messenger snubbing you in particular? Does he know you? Perhaps not. If he knew you would he talk to you, hang out? Perhaps not.

Riding a fixie doesn’t entitle you automatically to being cool with others.

Niether does having some specific bag.

My limited experience with couriers is that they are friendly; work hard, party hard. They did talk to me and were pretty cool. But I’m not doing the miles with them, and if I don’t share the same day to day experience (aside from playing in traffic for fun or as part of a commute), I don’t share that much in common. So, it’s a bit hard to bridge that gap.

You didn’t get a wave. Deal with it. Not that big of an issue.

Now, about the girls: you seem to snob it up on them too.. did you offer to help? Nope. So you’re just about the same boat as dude above.

Double standard.

Now about the car…. As they say, perhaps violence begets more of the same. Or not. But learn to ride and deal with those who will do wrong, in the manner fit to your personality, moral standard, and laws of local state in mind.