Abuse of Need before Greed system

So i have a question on this issue.. What is Need for and what is Greed for. I was just told by a GM that need is meant to be clicked if i want to sell that item to the vendor(http://img651.imageshack.us/f/gmacceptance.jpg/). I am just wondering how it works to be like that. I have just been needing every item and selling them like mad now though.

It really makes sense if you think about it. I need gold and almost everyone needs gold. Why should i allow the rest of the players on this game to gear up when i could have 10 gold from that item? I don't understand why i can not need plate gear. It is worth more gold than cloth gear and therefore i would almost need it more than cloth gear. Im in 264s so i am not interested in using the gear. However the gold is nice to gain. I feel weird since im the main person needing the items and usually win them all.

No.. i do not really play like this.. I have made multiple topics on this issue.. Everytime i will get people who tell me there no such thing as a ninja. They tell me if you can need an item it is not stealing however that is untrue.. I have been told this over 3 times in general by over 10 people.... I now have taken the stand to act like i am the person who does steal all items just to sell for gold and what do i see? I see people telling me how this is not the right thing to do.. Where were these people when i was saying how wrong it was? Where are the people that told me i should need everything that i come across? The point is not how i worded stealing items or how i am saying what people meant.. The point is that in general i am saying ninjaing is wrong in one and people disagree then i say ninjaing is right in the other and people disagree... Where is the group of people that agree with both topics?