Hard to know why its called "foot"ball. The origins go back over 100 years, and its based (very loosely now) on rugby. I don't know enough about rugby to say, but if I'm not mistaken, you can't kick the ball at all in rugby? American "foot"ball does have specialized players whose sole job on the team is kicking. We have a placekicker, who does "kickoffs" and Field goals. And a Punter, who kicks the ball much in the same way as Australian rules football players do - in fact, several Australian rules football players have come over to play American football as punters.
As far as the substrate goes, sand or gravel works. If you aren't going to be going heavily planted, but rather just 'having a few plants', as I do... anything works. I use both sand and flourite (a planting medium). But, the planting medium is working its way up and is a bit unsightly. I also have a pure sand substrate. The plants you choose will really determine that, but if you stick to the least demanding plants, substrate is completely irrelevant. It just needs to look nice and be heavy enough to hold down some plants.
Some plants don't do well when planted in the substrate (java fern, anubias, etc.). They need to have their rhizomes exposed to the water and water movement. In fact, burying that will result in it rotting.
