Quote Originally Posted by DJzen
ANY object can be sold. Even if you can't put it up for auction (which would be weird) you can offer to exchange it for gil with someone.

Food gives you nice little stat boosts, it doesn't last long though.
I'll have to disagree with these statements. Not everything can be sold and / or exchanged to another player. If the item is a 'ex' type item (which it says on the description) you cannot sell it or exchange it at all, unless for a quest from an NPC. (i.e. Beastmen Seals -used for BCNM)

Also, alot of food lasts a long time, meat mithkabobs are brilliant and they do last awhile. I know there are a few drinks for mages that last 30 minutes too.