Cause some people don't feel that killing is necessary to solve a situation. For example, I wouldn't kill if someone screamed at me, probably try to talk first and if that doesn't work and j knew I was stronger, then yes, hit them to make them realize how ridiculous they r acting right now. Cause sometimes, screaming doesn't equal that their a bad person. Everyone there is clearly afraid of what just happened. It's the fear that's making them crazy. Of course, if it's obvious that the person is evil or has bad thoughts, then yes, no hesitation and no mercy.
Maybe I've watched too many fucked up anime/mangas but I think killing someone would be fun. BUT I could never do it cause my parents are alive. ╮(￣▽￣)╭
How can some ppl be so kind? If I were in that situation and some strangers screamed at me liked that I would have killed them. With No hesitation.