So I hit level 35 today, and wanted to get a few Scarlet Monastery quests out of the way. I found a decent party, and was the tank. About half way through nearing the end, I accidentally need rolled a BoE 1 handed mace, and of course won it. I immediately apologized and offered for us to all re-roll for it. Everyone was fine with that, but we had this one mage in our party, level 32, who refused to re-roll as he thought that he should get it. It is true, while he hadn't even rolled yet, that he had won one or two rolls, and we were at the end of the instance. We all informed him that he was a mage, and that he didn't need it anyway. He told us that he wanted to disenchant it. This pissed me off, because i am a feral specialized druid, and maces are my area of expertise. I booted him, as we were almost at the end anyway, and he was being a hindrance on the party and we proceeded happily as ever.
These are a few rules for customary politeness in groups regarding need/greed rolls.
1) When an item is unusable by you, and is BoP (bind on pickup) pass on it.
2) When an item is unusable by you, but is BoE (bind on equip) greed it.
3) When it is usable by you, and is an improvement on what you have equipped, and is within five levels of you, need it.
4) When an item is usable by you, but is worse than what you have, greed it.
And remember folks, when you are a knob in a party, decent leaders WILL boot you. Also, if you get booted, don't open up a harassment ticket with a GM. It annoys both the GM and the guy who booted you