I'll agree, at the time DH II's preview numbers were crazy. But if you break it down, you'll see that with it's midnight start time, theaters were able to allocate as many screens as they needed to to accommodate moviegoers. My theaters in the DC/Maryland/VA area had showings from 12am to 6am. Roughly the same time Endgame and TFA had with 6pm - 12am showings. And the theaters for TFA and EG still had to show other movies in that same time frame.