The Thiel fellowship is for individuals who have a clear idea what they want to do and how they are going to execute it. It's for those select few individuals who think school will only slow them down on their path to making a difference. If you're already second guessing if it's worth it or not, before you've even applied, you should take a step back and think about how important school really is to you and if you're the type of person who believes in themselves so much you'd think it a waste of time to sit in a classroom.
That is not true. I know multiple Thiel fellows who either don't have a definite goal or have wildly changed their goals since becoming a fellow. A bit of soul-searching seems to be encouraged.
You also don't have to think college is a waste to think that being a Thiel fellow is better. You just have to think that a Thiel fellowship is better. That's not difficult, you're given some pretty incredible resources.