Games are really low scoring because of the one-dimensional offense. Passing sucks miserably until week nine, which means most teams sell out for the run, both offensively and defensively.
Ever watch an 8 year old little league tackle team play a game? It's excrutiating. Every once in a while one of those little guys breaks like an 80 yard run and the game ends 6-0. Otherwise, a majority of the game is played between the 30's.