Even before "of recent", I believe an award was attributed to MLG for taking over 100 posts to catch a magikarp. And there is nothing penalizing safari refs taking so long. The only way a battle can take for ages is for the ref to nudge dice for miss chances/paralysis/sleep/etc... (or for just a series of bad rolls) or if the players deliberately take longer. Since the players don't gain more points by taking a shorter period of time, it is in their best interest to speed things up.
In the game, there is no ref. In the anime, we never see a ref receiving payment. Making that comparison is, at best, difficult for the discussion of how the ref should be rewarded in ASB.
As Elf said. It is their choice. And, besides the fact that a lot of people do big battles (8v8), and very few do small battles, I'm left wondering why refs would make the choice to do a big battle.