You say people don't collaborate yet cite no source, so I can only assume you mean you wouldn't be collablrative. I can assure you I would be collaborative.
The idea that people in the wild are uncivilised savages is old racist propaganda.
You wouldn't exist because part of what makes you who you are is the society you've lived in and its social norms. If you had been born into a tribal society, you'd be tribal - or dead if you refused to cooperate with its culture.
Right but what says that culture would be violent and unproductive, rather than kind and productive? That's what I don't get. Runs counter to what I think is my nature and tbose around me, so I'd expect a position that has considered more evidence from your end.
Because a non-violent tribe will be destroyed by any violent neighbors it has. Even if it had a protected group of non-violent members, it would be militarily disadvantaged compared to its enemies with more fighters per population. And what are those non-violent people even doing all day in a world without any technological progress? Don't imagine you'd invent technology because almost nobody did much of that. If it was truly isolated like the Chatham Island Maori then yea, but they were eventually genocided by the mainland New Zealand Maori when they finally got to them.
I think you would be conscripted to fight whether you liked it or not, and inculcated with the belief that it's the right thing to do. Maybe even feeling shame are your unwillingness but forcing yourself to fit in anyway.