I understand that zoo can be seen as a place for humans rather than animals in one way. But as veternarian in the movie that you mentioned 'Garden, Zoological', has said, animals would love living in the wild but also admits that it is impossible in the real world full of builings and man made things which makes zoo an inevitable place for animals. Even though we all know the fact that animals should live in the wild, the world has changed so much for human but harsh for animals leading the zoo to be kept. In this way, zoos can be seen as a place not soley for humans but for animal protection and cure.