I've noticed that as I level my hunter and pets, they want higher-level food or more lower-level food to stay happy. If, for example, my pet dies, I revive him, and he's merely content - not happy. I happen to have a few mystery meats on hand, so I feed him those until he's happy, which takes maybe 4 or 5 (not necessarily mystery meat, but something lower-leveled), whereas he probably only needs one of the current highest food availabe for my level.
My question, then, is this: has anyone ever figured out what the most cost-effective food is for your pet? I know there are a lot of world food drops (making spending a lot on food unnecessary), and pack space is an issue, but if, hypothetically, pack space was not an issue, would it be cheaper to buy the cheap food and feed a lot until your pet is happy, or to feed just one of the higher-level food?
A pointless question, I know, but I thought I'd ask it in case anyone has any interesting insights.