Sad, and True

Which Calls (or Non-Calls) Create the Most Disagreements Between Football/Soccer Players, Fans & Coaches and Referees

Offside, Handling & "I was Going for the Ball"

Football (or in the U.S., soccer) players, coaches, and fans suffer from a number of misconceptions about laws or interpretations that cause unnecessary dissent, delay or distraction to ongoing play in matches. ...

See the whole article here, from Yahoo!

Kicking Back Comments: I have to agree with the author here. At the youth level, I would say these are the top 3.