As a player and fan, the worst part of soccer BY FAR is play-acting/cheating/diving/time-wasting etc. It ruins the image of a great, intelligent game that is played by some seriously fit dudes.
Unfortunately, it pays to be a whiny ***** in soccer, and the (mis)conduct of a whole lot of players in this World Cup makes a strong case for a little thing called "instant replay."
And here's a medical question for ya: how many times do you see a stretcher during an NFL game, where the players routinely get stingers, sprains, and concussions? MAYBE once every few games? Soccer players roll around on the ground when an opposing player looks at them the wrong way.