The Economics of Johnny Manziel

Johnny Manziel was recently accused of signing autographs for monetary compensation. For someone who brings in millions of dollars to Texas A&M, athletic brands, and television stations, it seems odd that he can't sign even an autograph for money. The restrictions on compensating college athletes tends to be supported by the intention of keeping the players students first and athletes second. In a multi-billion dollar industry it appears somewhat unfair that the actual players are the only ones not getting paid wages. But how would ending restrictions on wages and endorsements affect the sports, universities, other athletic programs, and professional leagues?