Yes, It's an opinion, if a customer feels they have a bad experience with a business then they are free to express it. The review site created the public forum for those reviews. If I went to papa john's pizza and hated it. I might tell people I know don't eat there. That's as far as It would've gone. Yelp the review site decided to give my opinion a megaphone. Why even let the site exist if you are only allowed to give positive reviews? Operating on the premise that only positive reviews are allowed renders the site and the concept of reviews pointless. If a food critic gives a restaurant a bad review the restaurant can't turn around and sue the food critic. What is this nonsense? Make sure your business is both professional & courteous, not just one or the other, otherwise be prepared for the consequences of bad reviews.