Unit cohesion is a must. That's why in shtf, small things like giving someone your m&m's or helping them set up camp. Will mean more due to the certin situation we will all be in
In combat you may hate the asshole next to you and think he is a complete tool but because he did few things like help you or you two.trained toghter or just simply he was around. It means you trust him more then your enemy.
Just one Grunts .02