Good question. Commercial operations keep their chickens in tight quarters. If chickens are crowded into real tight spaces, they have a tendency to become cannibalistic and eat each other. Many commercial operations debeak their chickens to stop this cannibalism. Our general guidelines on this forum for space for individual chickens take this cannibalistic tendency into account. That is one (not the only) reason we suggest more space for chickens than some other sources. Some people think we pamper ur chickens. Maybe we do.
I shared a small room with my seriously noisy and messy little sister. I understand the need for space! My chickens have plenty, and they don't peck each other. I think debeaking is mean, I wouldn't want to do that to my girls.