Because a lot of messengers ride ss and fg's.

I've got a job that would keep me in damn good shape if I worked more than 15 hours a week(most weeks all of it in the same day). I am a stagehand at my college's theater. I unload heavy **** from trucks, move that heavy **** inside, set heavy **** up, run around the basement of the auditorium like a chicken with my head cut off trying to find **** to fix stuff, load massive weights onto the fly rail system to counteract the weight of things hung on there(curtains, lights, any other random **** touring plays bring in) and pull the ropes to bring that **** in. After doing that for 16 hours in one day, your body is almost to the point of just shutting down. Everyone is being fueled by the donuts they give us in the morning, massive amounts of caffeine, nicotine, and the weed we all smoke before work in the morning to cure our hangovers from the night before.