How would Google know which postings are fraudulent and which aren't? The vast majority of these postings are fine/legitimate/consented. Why does it have to be Google that spends time and energy going after the bad actors, and if they don't, they become one?
In other words, I really don't see how Google is in the best position to figure out which restaurants have been posted without the restaurant's consent. I think that would be the companies putting up the original post.