In terms of how physically demanding the sports are, i'd say both Football and Soccer are actually a distant second and third to Rugby (either type). Rugby has all the contact and strength work of football (without padding) and adds in a minimum of around 6 miles of running per game. You could also argue that in terms of overall athletic ability and skills required that hockey (on ice) comes out ahead too.
Going off topic I know, but the point is each sport is different, and its not really about some imaginary ultimate toughness award.
Also whilst i'm at it, the World Cup has little to do with the actual sport anyway, its about national competition and the fans. As such how good the game is doesnt really matter, its just about nations competing and coming out on top. Trying to dismiss its importance by arguing the sport itself is stupid, is kind of irrelevant: the world cares, and the joy your country can experience from winning it is there for the taking, stupid game or not.