who says they even use their API? They could just crawl it.
Besides I'm willing to bet Yelp could care less.
https://docs.justia.com/cases/federal/district-courts/califo...
Would you bet your own startup on it? I wouldn't.
The alternative is waiting years, potentially NEVER to find a perfect, 100% risk-less (which doesn't exist, btw) startup idea that will help him become very rich.