What's up with all the rude foreigners in Canggu?

I mean I know Canggu gets a bad rep and all but I'm seriously shocked by how many rude foreigners there are in Canggu. People who don't say "hello," "goodbye" or "thank you" to the wait staff. Don't even crack a smile. It pains me because the locals are always SO friendly and nice.

Not to generalize but from what I've seen, it does seem to be mostly Russian/Eastern European people who act this way. Is this a cultural thing or what? I mean, how hard is it to say "thank you"? Seriously. It makes the rest of us foreigners look bad.