Saw this excerpt on a study that indicated that exposure to luxury goods can make people more selfish / less altruistic. It’s a bit of a stretch, but it could potentially why indicate that guilds / players who are surrounded by the best items any MMO has to offer tend to get a “screw the other guys, when is the next good stuff out?” attitude.
… not that MMOs necessarily draw in the most altruistic of people all the time, but a certain mindset does appear to creep in (or arise unchallenged) in a vocal proportion of end-game players.
World Class Villains 