The only reasons I would kick someone is for being purposely disruptive like pulling mobs before the tank is ready, (why anyone would wait in an LFR queue just to do things like that is beyond me but I have seen it) Flaming in chat, being AFK, and for ridiculously bad performance which would probably be intentional. Kicking for having cash purchased items is stupid and I would immediately start a vote to kick anyone who proposed it.