First of all, there was a big Gulag-supplied industry (google White Sea – Baltic Canal, also known as Belomorkanal, not to be confused with popular - in the USSR - brand of cigarettes). Second, even outside of Gulag, you couldn't just choose what you'd be doing: https://en.wikipedia.org/wiki/Parasitism_(social_offense) If you're not engaging in "socially productive" work, you're going to be relocated to unhospitable areas in the north or in Siberia.