1. You have to pay for EVERYTHING.... even the stuff you didn't know about, like insurance.
2. You miss having an entire summer vacation.
3. Just because you have a salary, doesn't mean you have a ton of money to spare. You can't just throw a thousand dollars around without thinking about it.
4. You don't stop having pimples.
5. You don't automatically become wise, mature, or rational.
6. Having your own house isn't as cool as it sounds. The buying process is horrible, things are constantly breaking, and the whole thing costs a fortune.
7. Even though you can buy and eat anything you want, you feel sick and get chubby if you eat a whole box of fruity bebbles every day.