I used to busk in morning rush hours in London; there is a pitch booking system, and there was simply hardly any competition for pitches at 8am. Sure, the money wasn't as good as it might have been later in the day, but having my pick of the pitches made up for that. The morning rush hour is also fairly reliable in terms of the traffic through stations, so once you've figured out which ones it makes sense to play at, it's reliable. Reliability is worth a lot to someone with regular expenses and mostly irregular income...