There's not that many people who come into the park for DAH and if it happens like the first time they did it. some will hang around the hub for night entertainment (and like most normal thursdays, 60-70% of none-dah guests will leave as soon as it's over). most will scope out the place so it'll feel more crowded but the ride lines don't go up.. like any other night you can still get in line up to the last minute before the park closes and then after that time, you need a lanyard to ride anything and only starbucks and casey's is opened for food you can purchase. The main street stores remain open (I think big top as well).
You can actually hang around the park all night if you want, they do not ask anyone to leave and it doesn't work like a party. You just can't get into any ride lines or get the included in prices drinks or snacks. I went to one DAH without a ticket just to have an empty MK to take photos of. I stayed about half of the night before I was happy with my photos and left. I plan to do it again, great way to get an empty MK for outdoor photos.
