Obviously food is on a unique level as I've been known to eat anything to effectively curb my hunger. I think it's a different matter when we are talking about spiritual fulfillment however. We are created with a longing for something that is real and eternal. When we attempt to fulfill that feeling with anything less than what God offers, it doesn't take care of the need for long. Sadly, I don't know that people always recognize the lack of fulfillment. We'll keep attempting to satisfy our hunger and never come to the realization that we aren't hungry for anything but truth.
Think of how much disappointment we could avoid if we could identify what we are really seeking and ignore the things that won't bring lasting satisfaction.