Backgammon, the Internet, and the erosion of courtesy

So I have Windows XP on my laptop, which has this bundled backgammon game. You play with real people around the world, and all you know about them is their primary language. I like it for two reasons: the mechanics and display of the game make sense, and you can't chat with your opponent except through preprogammed sentences. I do play occasionally on Gamesgrid, and I used to play poker on AOL, but among the reasons I stopped is that people are assholes. The gratuitous insults, the sheer nastiness of people who have an anonymous name is astounding, disturbing and seriously offputting. And I know that most of these people would never say these things face-to-face.
If you've played any online games with a chat option, you know what I'm talking about. I was raised to be polite, to be courteous, and since games were important in my family, I learned sportsmanship and graciousness at an early age. For me, that doesn't change just because I can't see and don't know my opponent. So why are so many other people just enormous assholes online? Didn't their mothers teach them any better?
There are only about 20 things you can say on the backgammon game I play, and they are all innocuous in and of themselves. Yet I am amazed at how inventive assholes are at communicating their assholeness with them. First and foremost, they leave the game as soon as it starts to not go their way. Whatever happened to determination, perseverance, leaving it all on the floor? Do these people leave their dates in the middle of the evening as soon as they think they won't get laid? Try harder!
Then there's the smiley face. ":)" It's astounding how irritating that is, and how nuanced in gloating in can be. So you won a game. Big deal. Play the whole match before you break that out. Or they say, "Good luck!" followed by "No". Why? Why go to the effort to trash talk this way? What can you get from it? I know, with my friends, I'm as guilty as the next guy for trash talk, over poker or whatever, but it's still friendly, casual, and I get as good as I give. Then, it's bonding. But this is so pointless.
I write this, however, because of the comment "It was luck". This is the canned chat line that just drives me nuts. Yes, backgammon is a game of luck, but also of skill. Most especially, it measures your skill in managing your luck. This is why you play to three match points, why you have the doubling cube, why you have gammons and backgammons (if you don't know the rules, look them up). And maybe this says more about me than the other guys, but I hate it when I beat someone game after game, match after match, and they keep sending, "It was luck", "It was luck", "It was luck". Especially when they keep making bonehead plays. Take some responsibility, for crying out loud. But more to the point, why be an asshole? Whatever happened to just saying, "Good game"? Win or lose, well-played or no, good luck or bad, it's courteous. And my fear is that while the Internet is a great connector, the anonymity of the connection is eroding a general sense of courtesy that was endangered before it came around. I see this same thing on comments on blogs or YouTube vids, and I find it disturbing and callow. I know anonymity is emboldening and I just wish that people would be emboldened in a different direction. PostSecret style. Honesty, inner feelings and opinions, sharing the strange, dark places in your soul and discovering that you're not alone. Instead, it seems that many people use it to let their inner asshole loose. To them I say, I hope it helps you, because you sure need it. If you can't find some bolstering influence online, you're not trying, and being shitty to strangers is unlikely to help you find happiness. And please, go back to the Intermediate level of backgammon: you're not cut out for Expert play.