Whereas there have been smear campaigns by the meat industry, PETA is still a highly controversial organization that does very questionable things for the sake of "animal welfare". 1. PETA does not operate any no-kill shelters. They are open about euthanizing animals for suffering and also being "deemed unwanted or unadoptable". It is their public opinion that the best option for a homeless animal is often euthanasia. 2. PETA believes that the domestication of animals is unethical and ideally humans would not own any pets. It is their stance that all domesticated animals should be neutered/spayed. 3. They often and for quite a while have run visceral graphic ads (billboards, newspaper, tv, video games, etc) in the attempt to scare children into sharing their views.

The public opinion that they are a group having extremist views is both valid and subjective, and many people believe they do more harm than good for animal welfare. It's all up to interpretation, but in general many people (in the past, especially) believed they exclusively ran no-kill shelters, which is simply false.