This game is tricky. For the last 25 years, the Michigan State game has always been the last game of the year, so trying to envision what kind of demand it might draw is tough because you can't really compare it to years past.
if we're 4-0 having just beaten Ohio State with a week off, and Sparty comes in 5-0 with Victories over Northwestern, Indiana, Arizona State, Central Michigan, and Utah State. This will be a top 5 matchup in a striped out Beaver Stadium, 3:30 kickoff, homecoming crowd, that will likely see ticket prices soar every bit as high as what we've grown accustomed to for Michigan or Ohio State. You'll wish you would have dropped 100 bucks back in June if both teams come in undefeated.
However, PSU drops the game to Ohio State, or god forbid Pitt, ... Sparty stumbles VS ASU or NW, and it rains? .... You'll get tickets for 40 bucks. The scalping scene for this matchup has way too many "what ifs" to feel confident around how much a ticket might cost day of game.