Sorry, might be me. Not sure I fully understand your response.
However, we are told that anything that ends before 6.00 a.m. is not allowed to be called an Allnighter.
Those that want an early finish can stay localish, as for being buggered without a car-what's wrong with Public transport?? 8 o'clock Sunday morning is better than 6 or 4 when your after a bus, surely.
Any way-it's all theory, innit ??