I've never been much of a fan of American football myself. Too much standing around with big guys smashing into bigger guys over and over without getting anywhere. With a bunch of Japanese robots, though, it's an entirely different game, especially since they seem to throw out most of the rules.
Whatever the rules to this game actually are (and I freely admit that the machine-translated rule book at the link below is beyond my comprehension), there's no escaping the fact that the ball is decidedly not round, which makes everything a lot more eventful. It looks like most of the (remote controlled) robots are designed with the intention of somehow grabbing onto the ball and then driving off with it, but it also looks like that almost never happens in the course of play.
Generally, this sport reminds me a lot of the Robot Hockey you see at RoboGames, where the speed and agility of the robots are often too much for their human drivers to handle, resulting in more of a haphazard free-for-all as opposed to an organized sport. The solution, obviously, is to just teach all of these robots to be autonomous, so that they can properly take advantage of reflexes which, after all, vastly outstrip those of their human creators.