I don't support animal rights, however I'm all for animal welfare. Many people have elaborated this quite well but I wanted to add to it a little ^^ Consider a scenario. You're a rich and benevolent person and you come across a homeless guy who needs help. One thing you can do is get him a place to live, a supply of food and education/work so he can stand on his two feet. The other thing that can be done is that you get him a personal spa, swimming pool and an entire range of original Apple products. Which of the two ideas actually seem plausible?
If we start treat animals like they're humans, we're doing nothing for their welfare but instead spoiling their natural selection and wild behavior. It's sad to see that people waste so much money on their pets and the wild which is no longer just about welfare and goodwill but it goes to extremes. People have campaigns for not letting dogs' hair be dyed because that means they're being forced to do things against their will--such petty campaigns can be exerted for more valid reasons than dogs having the freewill to decide the color of their coat. For instance, where my sister lives in England, there are a lot of foxes and there are reported cases of foxes entering homes and eating or mutilating babies. However, in name of animal welfare, they do not do anything to the foxes. It seems sweet, but it's actually costing human lives and it's no longer helping anyone but it's teaching the foxes in the area to prey on humans whensoever needed. This kind of attitude is detrimental for both us and the animals.