PETA wants to help animals, and stop people from treating animals in ways that are cruel. But they’re going about it the wrong way.
If you want to promote an ethical stance and get other people to adopt it, being a good advertiser is just as important as if you were trying to sell a product or get people to vote for you. Good advertising means, ideally, that (a) people will notice you, and (b) more than half the people who notice will be convinced by your argument.
The second point is important, and PETA fails miserably. If more than half the people who notice you end up disliking you, your tactics are counterproductive. You end up closing people’s minds to your ideas, even if the ideas have merit independent of the way you present them.
Sadly, a lot of people are too stupid to separate the message from the messenger; they will say they hate the animal-welfare movement, even if they are not cruel people and don’t wish any harm on animals, when what they mean is that they hate extremist proponents of it. The only thing PETA is effectively promoting is a negative stereotype of people who ‘like animals’, to the point where people get edgy and defensive when they discover a vegetarian in their midst. (It’s a bit like the ‘man-hating’ stereotype of feminists.)
My personal stance is that many of the animals that we use (for food, entertainment, research, etc.) are treated with unnecessary cruelty. I have taken steps to reduce the amount of cruelty that my own lifestyle causes. And I don’t give money to PETA or support any of their campaigns. I don’t believe that scaring, insulting, bullying, or misinforming people will improve the treatment of animals on farms and in labs. Judging by people’s reactions to these tactics, I think it’s actually doing more harm than good, and we’d move faster towards humane use and treatment of animals if we didn’t have PETA getting in the way.