My roommate eats all the food in the fridge, even though I clearly label everything.
Hungry In Houston
Dear Hungry,
Mooching roommates are a reality, and you sometimes have to accept the fact that they're going to clean out the refrigerator from time to time. This isn't always a bad thing, because it's going to save you some clean-up time, and your roomie might just be eating some of the expired crap you'll never touch anyhow. Less mess!
On the other hand, if Bob is scarfing down your leftover lasagna, or mom's care packages, I can see where you might get annoyed. One extreme solution is to pee in a pitcher (with your name on it), and let him learn the hard way.
Sometimes it's better to let it slide, especially is your roommate is a neat-freak who likes to do all the cleaning. Remember, you can always keep the choice leftovers in a styro-foam cooler beside your bed. The cooler can also double as a cheap night stand.