Who says she isn't addicted to that one already? She might steer away from whatever did a number on her mother, but it doesn't mean she's smart enough to abstain from drugs altogether. She's on record of making quite a few dumb decisions to date, if anything. And she clearly has some trouble controlling herself if she smokes her own shit to the point of tanking her own business.However, she also injects herself with this substance. Quinn may lie to other people, but why would she lie to herself and get involved in an addiction when we already know that she is actually against cocaine/hard drugs. This does not make sense.