Animals kept in captivity, and as in pet stores are bred for that, to go to being sold, to anyone who will pay, is not ethical treatment of animals, I am sure. I can only limit how I say that as I have not been going to pet stores. It may be better than slaughterhouses but that isn't saying much. There are other unethical ways animals are treated besides in slaughterhouses, and being held in captivity to be sold to anyone without any checks, while being bred for that, is certainly having unethical treatment of animals. Humans want freedom, animals should have that as well. And there are animal sanctuaries, but there should be many more, for animals who cannot have reasonable abilities to survive in wild environments to still have what freedom there can be, which billions of animals that there are in captivity would want.