Not reading this whole thread, but ..
My take on "Need" is that the option is there for people for whom the piece represents an IMMEDIATE upgrade. As in, they will equip it as soon as they win it (or as soon as combat permits). Not selling for Seals, not grabbing for an alt job, but an immediate, "I'm going to equip this now because it is better than what I have on" upgrade.
As such, I tend to roll Greed - which I take to be the "it is not an immediate upgrade, but I WANT it for some other reason : alt job, GC Seals, Glamour, Desynthesis, whatever other reason I may want it for.
However, if I see that someone has better gear than what they rolled NEED on, I don't call them out on it, I just start rolling NEED on anything and everything I can that drops in the dungeon from that moment on.
That's my take on the Need, Greed, Pass system. Its a holdover from the old "CAWU" definition on what constitutes a need : Can And Will Use. Use meant Equip when it came to gear, or if it was not gear, Craft With for crafting materials. At the time, there was insufficient overlap between the two (IE - gear that was used in crafting) that the few times where there was overlap were easily enough sorted out, usually by the crafting material wanting person passing until the next drop to the person for whom the gear represented an immediate upgrade.
