people who are similar often become friends or spend time together
“You want to stay alive in a zombie swarm? You go alone or in a small group, where everyone is of similar physical condition and weapons training. You never stop, you never hesitate, and you never show any mercy for the people that would slow you down.
That is what the military says we should do, and if I ever meet anybody who listens to that particular set of commands, I may shoot them myself just to improve the gene pool. When you can help people stay alive, you help them. We’re all we’ve got.”
― Mira Grant, Feed