I enjoy the broad grins while the two country butter squires are about ready to beat the shit out of each other. I think that they have seen violence all their lives and now that one day they will melt and be consumed.
Maybe they know they are fated to kill one another, and this is their dance. It has been so long, and they are such friends that it is a running gag between them, so they joke about fighting. But there is a kernel of terror because what if one of them throws a punch. They each know that this could lead to the fight that ends them both.