The point is they don't have to be successful to have teeth. A fast food worker probably can't afford a single day in court.

Absolutely. The Wikipedia article is full of them. What's critically important to know is the rules where you live because they're different depending on jurisdiction. If you are in California, non-competes are invalid. (Silicon Valley was built upon the Traitorous Eight.) If you are in Massachusetts, non-competes are valid (and you better hope you don't need a new job in biotech any time soon).

Talk to your lawyer for advice.