Seriously, though, help clean up the place. I pick up trash with a claw and trash bag set when I go hiking. Lots of wrappers, alcohol and cigarettes. You can't stop scum from littering the way you can't prevent violence no matter what law. It is just the nature of beasts. The least you can do with littering folk is pick up after them. They won't change. Treat them like animals you have to pick up after because they can't. And you have to or else they get what they want.