Lots of people used to do that for Jersey Boys in like the first two years of the run (myself being one of theme), but it wasn't like that extreme. I'd get up at like 3 or 4, catch the train to get to the box office by 6. I'd assume there were some who did that for Rent as well. Only downside is if you didn't sleep enough prior to that. Me and my ex got up super early to rush Once, got the tickets, and during the show, I started doozing off (not falling asleep but closing my eyes alot to the point my ex like elbowed me).