What does bother me about many of these organizations is that they actually kills thousands of animals. If the cats or dogs aren’t adopted within a few weeks, they are often killed (“euthanized.”) It’s like holding the animals hostage — adopt this puppy now or it’s dead [cue throat-cutting hand-motion]!
A growing movement, however, of “no kill” shelters has emerged, which only kill the animals in very unusual circumstances, such as when the animal is extremely aggressive or is about to die anyway.