look, roadies aren't rude.
it is simply that the uncouth "mountain bike" rider is incapable of understanding the subtle nuances of roadie verbal and non-verbal communications. if you would simply attempt to elevate yourself to a level closer to theirs (because honestly, ones such as you could never actually attain a congruent level) you may, and i only say may, begin to understand their actual message.
oh, who am i kidding; there are a lot of stuck-up ******s on road bikes. but there are almost as many on mtb's. and let's not go into non-bikers - that's just overkill...