soccer is wolrdwide. If NFl would be worldwide, there would be as many watchers as soccer.
Why isn't Football wordlwide ?
-Because there are many rules and most of people doesn't know quarter of them, then they don't understand a shit of what happens.
Soccer is simple sport compared to football
-I guess a soccer team has attackers and defenders ( left side and right side )
So players can play either on of those two positions.
Football on it's side, has more than 10 different positions with each specific actions to achieve = makes it more complicated, makes it HARDER to play as a team, makes it harder to understand for most of the people, which can bring disinterest.
that might also be a reason why soccer is more watched.
But my opinion is that we can't compare those sports, one is contact sport with high tactics required and the other needs extreme endurance and a godly will.
EDIT : The superbowl is the show the most watched worldwide by the way, ( right in your ass colo )


EDIT#2 American and Canadian Football for the win ^^