It's a film that doesn't make a great deal of sense. An interest concept but poorly executed so it turns into a jumble of nonsense.
There appears to be some controversy on the treatment of the Elephant. An animal rights group have released a video in which they state this animal is being mistreated as part of a training regime. The studio deny any mistreatment and say they had somebody from the American Humane Association throughout the filming.
Well as I recall (saw it a while back) the character played by Guy Pearce who you see right at the end has a shotgun and an ammo bandolier. All I am saying is considering the world has degenerated and you are faced with things like cannibals a pistol and a few bullets ain't going to cut it. Surely you would tool up and make it a priority to get a whole array of weapons. Think Mad Max 3 when he hands over his weapons in Bartertown. It's not like there wouldn't be a shortage of guns in the USA.
The film shows a fight for survival but I would argue that the father was poorly prepared to protect either himself or his son. In a situation like this wouldn't your gear up and go out of your way to get an arsenal of weapons together? One gun and a few bullets (which appear to be reserved for suicide) hardly seems to me like this guy is thinking straight or doing his job.
If you think this movie is perfection I can only assume you haven't seen that many films.