So many people hated this movie - why such a high rating?

Rating: 5/10 (24 August 2015)

As I scrolled through pages of reviews here, it seemed a majority didn't like it at all. Most agreed with me that the idea had some potential but that the final result was shallow and pretty boring. Visually it was striking, though.
If you know the British TV series Black Mirror, this looked like one of their episodes - the same kind of visuals, the same sci-fi mode, the same attempt to be ultimately unnerving.
But with so many people voting low, how did it end up with a rating of 7.7? There sure must have been a lot of 8-10s to outbalance all the 3- 6's.