It's unconscious, but reluctantly I have to admit I self-censor my work. My characters don't smoke, mainly because I don't and nor do the majority of my friends, but I'm also aware that I believe - I haven't asked her - a habitual smoker wouldn't get past my editor. In Nice Girls Do, Anna gets led astray into a coke-sniffing party lifestyle, but I was careful to show the negative effects this has on her and not present it as a sensible choice.
Would I get away with writing about a character who makes what are seen as negative choices - sleeping around, drinking too much, taking drugs, eating to excess - and presenting them in a positive light? I think not. I did once write a scene for one of my characters where she gets drunk and sleeps with a stranger which I felt was true to the character's distressed and confused state of mind, but it didn't make it past the editor. She felt readers would be disgusted and unsympathetic. I ditched the scene. Is that being PC, or over-sensitive to reader sensibilities?
I'm not sure. In retrospect, I'd gone overboard on making the scene too negative an experience and perhaps a sexy dalliance with a handsome stranger would have passed without comment. So long as they didn't smoke, of course.