Are you excited for NCAA March Madness 2015? While fans jump into office pools, fill out a bracket for fun, or ramp up to root for their alma mater, the tournament means big business for the National Collegiate Athletic Association, its corporate sponsors, advertisers and TV networks. On HBO's "Last Week Tonight," host John Oliver breaks down the myth of the student athlete and the NCAA's definition of an amateur athlete.

Oliver's March Madness segment begins with a dazzling video hyping the annual college hoops tournament, followed by the news that the two-week event brings in a billion dollars in ad revenue. "Everything about this tournament is branded," Oliver says, including the championship-winner moment, which is presented by Werner Ladders. A lot of money pours in, but none of it goes to the athletes because of the rules set up by the NCAA, he contends.

"They're not employees; they're student athletes," Mark Emmert, NCAA president, says in several clips shown on the March 15 episode. But they reportedly come under some harsh rules. After UConn won the NCAA tournament in 2014, star point guard Shabazz Napier admitted he and other players had at times gone to bed hungry due to meal restrictions enforced by the NCAA. Following Napier's comments, the NCAA approved new rules for unlimited meals and snacks for athletes.

Other controversial NCAA rules apply throughout college athletics. College football is highly profitable for many schools and the athletes face restrictions and have to balance practice, games and school. During Super Bowl 2015, Seattle Seahawks cornerback Richard Sherman and defensive end Michael Bennett discussed the problems and concerns they had with the NCAA rules. "As a student athlete, you don't have that kind of time. You wake up in the morning and have weights. Then you go to class. Then you might get a bite to eat, then you go to meetings and then you have practice. And you have to try to get all your schoolwork done," Sherman said in an interview. The cornerback said he ha a negative balance of $40 while playing football at Stanford University.

You can watch "Last Week Tonight with John Oliver: The NCAA" below.