You would be very hard pressed to find any MAJOR college sports program that does not require you to contribute to an athletic foundation/excellence fund of some sort. This really shouldn't be all that surprising.
Also keep in mind that general contributions to athletic funds are tax deductible. Tickets are not. It is a way for the Universities to get their money and still provide an incentive to the purchaser. That is one of the primary reasons you see the contribution requirements ending up higher than the actual ticket prices in many instances.