Being mostly concerned with the consumption of brains and having a general ambivalence to the existence of a god, what type(s) of sports would be of interest to a society of agnostic zombies?
Brainz Is a gruesome sport. It is also extremely popular. The game is played between two teams. The goal being to steal all of the opponents' brains. No player can however EAT any of the brains stolen, they must stash it in their own cranial cavities, obviously this means they must first undergo the same procedure any other player does, to make the top of their cranium removable. As the game progresses, players either become much more sluggish and unresponsive as their gray matter is stolen, or must use increasingly more care to avoid dripping any of the brains in their increasingly full head.
Common strategies are to use one player on which to stash all the brains and protect him while hunting for more. Another strategy is to eat the opponents brains (to the delight of many) when it is clear getting back to your own team is impossible.
A favorite is when a zombie team is set against a yet-to-be-zombified team. Often the non-zombie team will win, as the zombie team will unavoidably proceed to having all their players disqualified for eating the non-zombie team.