19. Potato Stix
Potato Stix are just potato chips, but harder to eat. At two in the morning after your day-long trip across the state, you can convince yourself there is something special about them though; we certainly have. Soon enough, you'll realize the only thing special about them is how hard they are to clean out of your car seat, when you drop a handful as you come to an unexpected stoplight.
You think you've learned your lesson, but it's only a matter of time before you make this delicious mistake again.