I don't think you/we can necessarily assume it's only NU fans who are doing this.
Next year our "home" games are Michigan, Minny, Oregon, Purdue, UCLA. If I'm an Oregon fan, it actually makes very good sense for me to buy season tickets and sell the others - will probably be able to make th money back (or close to it, even if not at a profit since that's not the main goal).
Frankly, this is why Ticketmaster implemented "dynamic pricing" for some of their shows, where prices can fluctuate in real time. TM publicly argues its their way of deterring brokers, without acknowledging how much more they are making in the process.
I will say this: I don't begrudge Northwestern offering of premium seating, boxes, etc., to meet demand. But I also think Marks and Jackson both made some disingenuous remarks about what they are "learning." Yes you need to offer different options and experiences...but I'm personally never going to be earning "premium box seat" money. When I last checked in August, the seats that were still unsold in the stadium were the "premium" South End Zone seats. The first section to sell out was the North End Zone - the one for us peasants. What does that teach us/them?
I, quite literally, represent the fan who loves to go to games, but realize the reality that I might just get priced out...and if NU can't sell out Ryan Field 5-7 years after opening it and the novelty/curiosity wears off...it's not like I'd be coming back; or I'll just go to the occasional game when I can buy $5 tickets off the secondary market...if NU wants to just make this a transactional relationship, so be it.