I can't believe I have to post this, but there have been enough complaints to where it's warranted.
1) If you don't need it or can't use it, don't Need Roll it.
2) If the loot threshold is set to Rare, don't ninja all the greens. Someone else may need one of those items.
3) If a person wins a roll and it's something they can actually use, don't complain about it.
4) Being an enchanter does not mean you can Need Roll everything. If you're trying to roll for something just to Disenchant, Greed Roll.
If I'm not in the group, I'm going to need to hear the complaint from 2 other party members, 3 in total, to follow up, otherwise I'm just going to assume you're pissed because you didn't get the roll you wanted.
If you're caught violating these rules, you will recieve one warning. After that, you will be free to find another guild that puts up with this mess, because you'll be kicked out of this one.