Average Americans hate this movie
It is interesting to read that all these negative comments about this film are almost exclusively always happen to come from dumbed-down average U.S. audience who was apparently expecting to see yet another Disneyfied fairy tale artificially manufactured in order to thrill their families and empty their wallets.
This film mostly portrays the everyday reality that some of these animals face and is made for the sole purpose of us humans getting to know that these kind of things happen, and thus force us to act and stop this abuse. So anyone who can't stand this and needs to walk away from the theater because their fairy tale projections are not met, is the ultimate enemy of these beautiful creatures that they wanted to see happy in a first place.
Unlike typical Hollywood trap, this project was made to have you think and act on the basis of information you received, and not to leave the theater smiling like a happy idiot while forgetting all about it two days later. It is film designed to help these animals, and not to have you spend money on useless toys and products associated with this movie, which is a norm for the typical Hollywood happy ending fairy tale.
Americans should grow up for once, and realize that the world doesn't revolve around their artificial expectations of warm and fuzzy feelings they are so addicted to.
By the way, this film has a happy ending, and the "violence" against animals is quite mild by any reality standards.