I say this as someone who was very heavy into PvP in UO. There's a reason for this. Most PKs wanted to be wolves. Very few players want to play a game where they're sheep.

I spent most of my time tracking down the wolves and fighting them. So so so many of them would run away the second anything approaching a fair fight presented itself to them. On my shard, over time there was a group of us representing the spectrum of "good guys" and "bad guys" but who weren't just trying to be assholes who bonded & became friends. When playing in character we'd fight each other. And then when some band of asshat PKs would go around being jerks, we'd out of character join forces and go stomp their ass.