I think we're wired to do this with all sorts of things. I used to spin coins in a makeshift arena to see who would emerge as the over-all winner after multiple rounds. And I recall Lister in Red Dwarf blowing bubblegum bubbles: "ten and three quarters! Plus five for not breaking. The Browns are going to have to do something quite sensational with their last bubble..."

Interestingly, I think that in conkers the player doing the hitting is rather more likely to break the other person's conker, rather than have their's broken, unlike what he says with the eggs. I wonder if it has something to do with where the collision happens on the conker.