It has permeated our culture and ruined it as far as I am concerned. People are less interesting and dumber as a result.
I think the people and culture are dumb regardless of football. The game itself is like any other sport in that it is poetry expressed through the physical. And this poetry, like any other art should be admired for being a uniquely human trait...and frankly, one of our better ones. I take nothing away from the talent and competitiveness of the game.
That being said it gives average american males something to do. There's not much outside of work and sports except the military to provide distractions to men. The elites can't have them 'unaccounted' for and as such capitalize sports to a rediculously high degree.
The most revered quality in men is their submission to authority. It is highly prized by the elites and is reinforced in all of the "societal" human pyramid style authoritarian structures, the army, religion, corporations, politics, etc.
