The worst is when you see a class who's buff you really want (yes you, Smugglers!) and you buff them with yours, then stand in front of them, waiting for them to buff you back. When they don't, you buff them again. And again. And then you bounce up and down in front of them and buff them again. Then they turn and run away.
I guess these people are either jerks (won't buff me back cuz it doesn't benefit them), stupid (can't put 2+2 together that they are supposed to buff me back), or newbs (don't know how to buff me back). I suppose I could send them a whisper and ask for the buff but, I'm lazy.