PETA not so ethical when it comes to shelter animals.
I am on board for the humane treatment of animals whenever and wherever possible, including food animals and research animals. I have multiple pets, all of whom I adopted or took in as strays. I believe firmly in spaying and neutering, regular vet visits, holding pet owners responsible for their actions and humanity's responsibility to balance our needs and desires against the health and well-being of earth's living creatures.
That said, I find what PETA does largely appalling because their excesses and hypocrisies make it too easy for people to dismiss the legitimate concerns about the treatment of animals. Moreover, their philosophy about animals is often anti-scientific and illogical, and their goals, if met, would mean unmitigated disaster for the environment and the ecological balance of this planet. When one's belief system is based so thoroughly on half-truths and fallacies, even one's reasonable messages are bound to be lost in the barrage of refutations.
Like anything else in this world, moderation is key. I hope that conservationists everywhere become the real face of environmental responsibility and push the extremists on both sides out to the hinterlands where they belong.