This reminds me of something I've been contemplating on my morning commutes lately ...
Roadie guys (ok, women too, but there aren't very many, so I'm generalizing) around town know me as a racer, etc. They see my team kit and often know who I am and usually wave to me or greet me when we pass going opposite directions.
Since I started commuting on my Mule bike (a home made hybrid- photos in the commuter forum), I'll pass the same guys I occasionally train with on the weekends. There's an early morning ride from a bike shop in midtown that a lot of them go to. Since I'm on a goofy looking bike (not calling hybrids goofy at all- just my hybrid) and not in a team kit, when I wave at them, the most reaction I ever get is a chuckle and occasionally a slight wave back (if they'll even make eye contact).

What gives? How about being nice to everyone instead of just the people you think are "worthy" of your greetings??