I don't think there's anything deep about it. They do what they want because it makes them feel good. They're like humans without the self control and moral standards. Human life holds no value to them, but the thrill of the hunt does. The stalking, the chase, the bloodlust, the fighting, the bragging rights. I expect it's no different than people are when playing videogames to some extent. Satisfying a natural impulse for competition and/or combat. To overcome, and to dominate. It's just that Predators prefer the real thing.
There is an intelligence there, but they're still a highly impulsive species. They do what they want, simply because they can. They're warriors, what they want is to eat, drink, fight and make the sexy.