Do the items you find from loot do anything other than just get you money at a vendor? I always sell them all and even the special ones I get from hunts.. is that bad?

You can get Bazaar Goods from it

There's no real point in keeping it most of the time. The only exception i can think of are the two hi arcanas montblanc gives you. If you keep them for a while then you can sell them for tournesol or other weapons.

Read this:

Loot and Bazaar Guide

Hello all of you people out there! How can you say 'Loot' is not important?! 'Loot' is what gets you a lot of gil! Using the techniks 'Steal' and 'Poach,' you can obtain more and more items to sell - 'Loot.' The 'Loot' is not important, besides a few items for various quests, so you sell it all to obtain gil to buy anything you desire.

You may think "Yeah, I don't need to sell loot to get gil because I kill things to get gil." Selling your 'Loot' will result in even more gil for you to buy even more things. The exceptions (I may miss a few out here)'Teleport Stones,' 'Gysha Greens' and a 'Snake Skin' which is used in a later quest for some bizarre reason. If you are a Sky Pirate, like me, of course you can always seek out treasure in the best places!

yeah I knew selling loot gives you bazaar items and alot of gil.. I was trying to ask if any of the items were for quests or other things like that but balthier answered that! thanks