Some years back I would spend all day at Wachusett Mountain (MA) on Wednesdays. I'd ski from 9:00 am till around 9:00 pm. I stayed to ski with the night race league, which I think is the biggest race league program in the nation. They certainly had a large number of skiers at night all over the mountain, not just on the competition slope.
Around 5:00, mountain ops would run groomers on some trails to refresh the surface for the night session, depending on which trails needed it the most. Most of the mountain was lit up at night for night skiing, so some trails would definitely need grooming if the day had been crowded.
Ski patrol would put up a rope while the groomer did its thing on each targeted trail. Large numbers of skiers would congregate at each of the ropes, waiting for the drop. Patrol would station their people at the top to guard that rope until the very last moment, and when they dropped it there was a genuine Chinese downhill. It was crazy. These were adults.
I assume Wachusett still does this, and that skiers still do this too.