Originally Posted by Unregistered

I did not know that about friends. I will admit that I have been doing much of the friend shuffling, trading up to get heavy hitters most of the time. Kind of quirky if you ask me.

Yeah, the game rewards you for having friends. Both people get +3 to stamina for every friend. Leveling up usually gives you a 6 stamina boost because you get 3 from the level and 3 for the new friend you will almost undoubtedly pick up.