Ninja loot confusion.

[UserHere]

Sometimes, when I roll greed on "of Scouting" gear, which is listed for NIN only, others (non-ninjas) also roll and get it instead. Can other classes use this gear. or are they just rolling to vendor it? (I pass on everything that's not listed for my job)

If you're on Ninja and want said Ninja only gear roll NEED not GREED.

[Iscah]

The simplest version is that Need always overrules Greed, regardless of what you roll.

If you're the only ninja in the group, Need is a 100% guarantee you'll get that scouting gear. With another ninja or potentially dancer in the group, if you both roll Need, you're only competing against each other.

Greed is the all-equal "second chance offer" if nobody rolled Need. Everyone has equal chance of winning it, regardless of their class.

(If I could roll Need on something but I don't actually need it, I'll pick Greed so I still have a chance of winning it, but everyone else has a chance too.)

The names are unfortunately rather misleading.

[Krojack]

It's very common to roll 'Greed' on dungeon drops, because they can be turned into Grand Company seals. The current drops, from expert dungeons, can be exchanged for 1500 seals a piece.

Alllll this. I roll greed on all dungeon gear to turn in for seals. I eat though company seals like crazy so I'm always needing them.

[tdb]

The names are unfortunately rather misleading.

Not so much misleading as open to interpretation. I think "need before greed" is something most people can agree to (and not just in the context of video games), but there are different opinions on what constitutes a need. One extreme is that need should only be used when the item is a direct upgrade to your current class; at the other end it's perfectly fine to need anything the game allows you to need even if you're going to sell the item. And then there's the whole debate of whether you can have actual needs within a video game.