Never attribute to malice that which can be adequately explained by stupidity.
Here's the thing with review sites; the reviews are not made by people qualified to write reviews. I've seen one-star reviews on Amazon because the person bought the wrong item and they didn't like the return policy. I've seen one-star reviews on Yelp because the restaurant didn't use recyclable takeout forks.
It's really dumb to put any value into the star-rating system, and yet people do it. I only look at the stars if there are 40 or more reviews. Then at least a few people with some common sense got a chance to weigh in.