Snowflake is a newcomer to Underworld, and to ghouldom. He showed up a few years ago after being kicked out of Rivet City. Because he had nowhere else to go, Underworld took him in. Snowflake's main skill is as a barber, which isn't much use to anyone in Underworld. Lacking any other way to pass the time, he's taken up jet.
He takes Jet as a result of boredom, which doesn't exactly contradict Murphy's statement that Jet barely affects ghouls, since the extent to which it affects Snowflake is unknown.
Snowflake insists he is a stylist and not a barber. This is nearly the opposite of Butch from Vault 101, who insists that he is a barber and not a hairdresser.
There's a piece of presumably human gut under Snowflake's table and some blood nearby, which leads to thoughts as to what else he cuts aside from hair. In dialogue, he mentions that half a ghoul's haircut is cutting off dead skin, and this may be what accumulates on the floor between cuts, rather than hair as in a normal human barbershop.