I'm with this... I'm usually in a group of 2+ and my friend will basically fight 5+ zombies by himself with no risk/danger while I loot/lookout, I find that's what helps make the game more of a PK fest.
On a side note rofl if anyone has VSS ammo i'll trade you for .308 ammo :P I know the wipe is coming soon, but I just don't wanna lose my favourite rifle.