I hate grinding my way up to nowhere but boredom.
I hate lag.
I hate immature/rude players.
I hate whiners that b'awww and complain too much.
I hate hackers.
I hate its addictiveness sucking the life out of me.
I hate big-ego players who think they are so great and godly and everybody else should bow to them.
I hate drama in an MMO, though they could be fun to watch sometimes
I hate hardcore competitive pvpers who think that anything that isn't bound to a tourney rule is taboo and forbidden during casual and fun play.
I hate BR huehuehuehuehuheuheuhe. (no offense to any Brazilians who actually play normally)
I hate items that give extra content through cash shop only.
I hate class discrimination.
I hate you.
I hate shout spammers who think they're funny, but are only ridiculing themselves.
I hate website spammers.
I hate when people who don't help out newbies/first-timers.
I hate when GMs don't do their jobs properly.
I hate scammers.
I hate MMOs.
...But not really, they're fun