Honestly I can't stand people like that.
A chicken living out its life in a backyard, even if they're raised solely for eggs and/or meat, is MUCH better off than if it were living in some factory farm.
Some people are even against domestic animals completely... Because my dogs are totally slaves. They get fed high quality food, they get to have the run of the house & yard, I play & exercise with them daily - they have an entire basket full of toys, they only get trained via positive reinforcement, they sleep on my bed or wherever they please. I'm totally going to hell.
*cough*Peta*cough*
Also annoys me when vegans try to make their pets vegan too. Whatever, you want to choose that lifestyle? That's your choice. But don't force it on your pets, especially when they are obligate carnivores. aka cats.