Bear boxes

Here in bear country, all the campsites have bear boxes - big, metal, bear-proof boxes for food storage.  

Ok, so the bear can't get the food, but he can still smell it.  I'd figure the bear would come over and be all disappointed that he can't have my peanut butter, then look around and think, hmmm, what's the next-best thing to eat around here? (hint - it's in the tent).

I've been told that this is not how it works.