There's no excuse for rudeness to FA's at all, but then again, what I really hate are the FA who's attitude is that they couldn't give a s**t about the passengers (I might add, I have normally found this with US airlines...). As an FA you're there to do a job, which is primarily concerned with the safety of the aircraft, and the comfort and well being of the passengers. If you don't like it, go and do something else !!!
By the way, in my opinion Virgin have the best (and cutest) FA's around...always helpful....