I don't believe athletic competition is zero-sum. The status gain of the winners isn't offset by a status loss of the losers. In fact, the losers often come out with a gain in status, assuming they play well.
Another way to see that it's positive-sum is as follows: A close-fought game results in more status for both sides than does a rout. If the game were zero-sum, that status had to come from somewhere. But in fact, if the losers play better, both sides come out better than if the losers lost, badly.
Conclusion: athletics and similar competition is positive-sum, and the size of the total status gain depends on the talent being displayed.
Status is relative by its essence. So, if some forms of direct competition seem to raise the status of both competitors, somebody else has to lose. It only needn't be one of the direct participants in the match. You're right that both competitors may gain status if they both play well, but the very meaning of "well" is decided from comparison with other players in the relevant pool; if you play better than they usually do, your status grows at their expense.
Also, it is not universally true that close-fought results get positive status change to both competitors. Close win against a low-status outsider is often a status loss for the winner, even if the loser played well.
The other day, someone did something I didn't expect. It was something many people have done before; something that I thought of as very normal, but that I in no way understood and had not predicted.
As I said, this had happened many time before, so I wrote it off as "me not understanding people" or "people are weird" for a second, like I usually do, before realizing that "bad at" really means "lacking basic knowledge", which I had never realized before.
And then I thought "I should ask someone who is different from me why people do that, and eventually someone will have an answer."
But many people will have many more questions like this. So, what have you observed people doing time and time again, but never understood? Or something that you only understood after a long time or asking someone about it?
And can Less Wrong tell us, not necessarily why (I for one can make up evolutionary psychology fairy tales all day if I want) but what conscious thought process occurs behind these events?