Personally I'm seeing it happening a lot nowadays, mostly large vessels killing friendly to them NPCs around to grab bots/bats. Technically they should be expelled from the player factions they are belong to, it's an act of treason after all, intentionally killing of his/her own allies, NPC or not. If they don't seem to care about RP and take any opportunity to win in PvP... I guess then there should be a rule restricting such behavior.
