Just asked my brother-in-law, a recent VaTech grad, how much he paid. Games were $7-8, seasons were around $50-70. Similar for my wife, who went to Michigan (albeit, around 10 years ago). Like GoCuse wrote, I think students get in for free at Penn State.
The thing at Syracuse is, it's not like those seats are being taken from anyone. There's never been a time during which tickets were in too high of demand. The only loss is the actual ticket values of those students who would otherwise purchase them. To gain is better atmosphere, increase in concessions (not sure how much of that- if any- goes to SU), and the possibility that the above improves the atmosphere and draws more non-students.