Get 'em tiger. OCD-types can't imagine how anyone would live their frickin' life next to some beautiful machine. It's a tool. You bought it, you can ruin it if you want (assuming your parent or school didn't - then that would be rude). Fools leave their DeWalt drills in the rain too.
If I were you I'd invest in a moshi keyboard cover at least. This will block the blueberry muffin crumbs and milk splashes (who drinks milk? how old are you?) from your keyboard internals. Replacing your keyboard on a unibody is a b$&ch.
It's better than sugared pop which rots your teeth and makes ye' fat.