It seems to me that it was a combination of Moe, and what other people have alluded to, the relationships with all the other people in the class. The whole "best class ever" thing they were selling.
I believe Cribby said in another thread that our NIL package was more $ guaranteed/overall. The a2m offer was structured with incentives and conditional on staying 4 years. Not to mention stuff for Moe the Hutt.