If there was conflict and it came down to you or your neighbor, whom you've had a long, peaceful, and cooperative history with, you would choose yourself. Working in groups is beneficial, but when shit hits the fan it's every man for himself. This was extremely evident at the beginning of the pandemic when guns and ammo were flying off the shelves in my country faster than they could stock it. Society broke down as we all stayed in our homes, and our base instinct was to arm ourselves. We weren't buying guns to protect our neighbor lol we were buying guns in case we had to shoot our neighbor. Groups break down quickly when things get down to the wire. I'm not saying we haven't ever worked in groups or that it hasn't benefited us, just that it's not our core programming. We do it for convenience because it does benefit us, but when things stop being convenient we stop being peaceful. There is lots of evidence of this, as well, if you are open to having your mind changed.