I think a lot of the violence aspect is due to modern culture. We humans are taught our entire lives to not be violent, and it takes time to break down that barrier. Just like a well trained dog can be abused repeatedly without starting to fight back or even bark, because they’ve been trained to never bark or bite.

I don’t think there’s any reason to believe a human in a survival situation has any less capacity for violence than any other mammal, we’re just too similar to them, and violence is so ingrained in our reptilian brain. I just think most people are never pushed to the point where they behave like a cornered cat fighting back.