What Tyger is saying is that, how'd I put it, when the game encourages some kind of player behavior, the players comfortable with that stay around more and those uncomfortable with it leave early enough to not necessarily be counted. This happens with champions online: The game's lore is very mary sue-ish and you see things like glowy-stealing(game encourages it). Because the player is worshipped constantly to an extreme and because the player can do things like steal from others fighting for a quest item(the glowey) you end up with more rude individuals than nice individuals. The % of nicer players lowers as nicer players get tired of it and leave. The same can be said of those who are put off by being treated like mary sue; they leave early enough that no one really counts them.
You end up with players who either don't notice they are treated like mary sue, those who play only cause they feel they have no other options, and those who want to be mary sue and want to be treated like kings. While you still get people who want a fun game and want some challenge, you get a lot playing CO who are just in it for a giant power trip easy mode. The game's community imo is the way it is because the game encourages those kinds of vices.
That can honestly be said of any game though encouraging some form of bad behavior(of the soft variety) in it's players. At least when they are playing the game in question they end up like that while playing it :/. To them, the bad bahavior is part of the game in question.