I agree, but we're all just human, and most of the time it's not truth that comes with rudeness, it's just more rudeness and a lot of opinions. Worse, people seem to think that being rude is a way to broadcast your important or genius, when it really does nothing of the sort.
I'm also not talking about "expecting respect", I'm talking about people who cross basic lines of conduct. "I don't feel I'm being treated as well as I should," is not in this, and yes, people who expect that need to ground themselves in reality a bit.