How late does drunk singing on the bus become OK? If you want to say never, that’s probably correct. But I was on a late night bus over the weekend, and a drunk couple were singing their hearts out to a song I didn’t recognize. It was more charming than obnoxious. But if that had been rush hour on a Tuesday, it would have been horrible. Maybe it’s more of a continuum, slowly becoming less bad as the night progresses, than a switch.