Agents get 2-4% of player's contract salaries depending on the agent. Agents make their $$$ off athletes endorsements.1.5 or whatever, the government gets it's share, agent, etc gets their share. Not a ton left over if he doesn't get that second contract. He's basically a AAAA player now. If that was a good plan so be it. To me more investment in college could've yielded a better reward for both of those guys.
Your opinion is fine but it is tilted to what is best for JB, SU hoops, and us fans. Ennis doesn't have to go to class, do his class work and can work on his craft more easily not playing college hoops. Playing 2-3 zone another year does not help Ennis get better prepared for the NBA it helps SU/JB/Us fans.
Every player who decides to leave early makes the right decision because they want to become professionals. Playing college basketball is fun I am sure but on the first and fifteenth you don't get huge checks.