By keeping animals, where they're not supposed to, you're abusing the poor animal, those around you, and yourself, and you're disturbing nature. Yes they "should" treat them better, but what is way more important, is that nobody should keep animals they don't have a purpose for, especially inside the house, they cause health problems (animal hair prevents absorbing nutrients) and they can be dangerous, and if not, they're not animals anymore. I don't hate animals, and I've helped animals when possible, though I've found the hard way that even then, you should not overstep your boundaries, interfere too much and disturb their natural way of life. A lot of the times, most animals, don't perceive life the way we do, and applying the same logic and ethics only over-complicates their lives, and possibly ours, for no good reason; that's why they take out (or used to anyway) animals with severe injuries.