1) Whenever Alliance bumps into Horde or Horde into Alliance on a PvP server its pretty common for one of them to start and attack on another just for the sake of it. I remember walking some time ago with a Pally through Ashenvale and saw a Troll Hunter 27 or so ( I was 31) I didnt even targeted him and just walked by but got shot anyway... Divine Protection, ignore pet, Judgment of Life , Seal of Command. He tried to kite me but instead of turn around and run he walked back and spammed con shot when I was next to him xD. He droped dead and I just moved on

2) as stated above, less then 50% of WoW Players read forums properly and post whenever they need to QQ. "Multibox = cheating" likes to walk in pair with this

3) Hero-syndrome when one things he can take on everything

4) SImple Envy

5) Plain stupidity

6) Lack of imagination