I have the distinct impression that Yelp's corruption is so widespread that it is evident even to the general public, and a good rating in Yelp is approximately worthless and has been for some time. I'm sure there's some non-zero value, but if the businesses that are paying for good Yelp reviews are paying any significant amount at all, they are getting ripped off. Which, given the circumstances, is a bit of karmic justice, I suppose.