The game is a Business
A brutal business. Organized football leagues at the professional and collegiate levels make money taking advantage of the physical talents of others. It is almost guaranteed that players will injury at some point in their career. It is of particular ethical concern in the college game. Hundreds of millions of dollars exchange hands every year as a result of college football and students are not compensated as per NCAA rules.
Here is a video of former NFL player Mark Schlereth's commentary on the NFL's business: