1. I'm not at all surprised, I've known this kind of thing has been going on and I'm sure it's largely underreported. Heck, the previous place I worked constantly asked employees to give five star reviews to the app we wrote. Multiple places I worked have asked us to write good glassdoor reviews.
2. It entirely undermines the integrity of rating systems, as only a couple extreme reviews can do major damage to a rating. This is the marketplace's problem as much as it is the community's, and some marketplaces (e.g. Amazon) have taken up suing fake/paid reviews.
So I'm not surprised, but I think it's abhorrent and does huge damage to the marketplace as a whole (I'll watch fewer movies if I can't trust ratings).