You and @Hawk would know a lot better than I would, but like you said, I'd highly doubt that the masses show up. For Sugarbush's sake, I hope they do and I hope they buy a ton of food and beverages. But I'd be stunned.
Historically what has closing weekend looked like? I would think it's just the die hards at that point. Ski for two hours, party in the courtyard for 2 hours. Take a nap and then enjoy dinner.
Yea...that's pretty much what it has looked like. Very variable depending on the weather. But never really overly crowded even on nice sunny warm days. FWIW, they did do some "Free" skiing closing weekends under Win. So that part is not without precedent. I don't remember crazy crowds back then. And today you have a smaller pool of people to pull those "free" skiers from with so many people already being Ikon passholders.