Sneaky Issues..

We are having some sneaky issues in our house.  Kids that for whatever crazy reason decide to sneak cookies, or candy, or something of those sorts, hide it, and eat it.  I can't even figure out the reason for this problem.

Is it that they just don't get enough, so they feel the need to sneak?

Is my punishment for that not harsh enough?

This isn't the first time, and it's about to drive me batty.

What is a good punishment for the kind of behavior?

Anyone have any insight?