I love playing on the PvP servers. I don't ever attack first, but I do kill them or atleast try and kill them if they attack me. I rather enjoy going around and scaring lower level horde and following them around. If they draw too many NPC's I usually kill the NPC's for them or I just help them out in general because I am bored. I have only had one horde help me out, and that was after killing me 3 times. After that he followed me around and told other horde to leave me alone and he killed NPC's for me. It was rather fun.
And if you aren't on a PvP server, can you not raid then? Because raiding is sooooooooo much fun!