Drink and party after show, not before

I don't know if it's just me, but the last night of rehearsal when he tells them take the rest of the evening off and be back 10am next morning for the show and to give it their all. To really get ready to do their best, they should've rested and gotten a good night's sleep. Instead, everyone partys and gets drunk. The night before the show? They should've done all that the night after the show, like to celebrate and everything. But they do it the night before, and then there's friction and a big conflict and people getting all upset and angry, which obviously will get people even less rested, centered, and ready to give it their all the next morning. Oh well, I guess they needed to do it that way for plot purposes so we get the climax conflict between Dorothy and Mr. Dillon and etc.