Couldnt do it. But then I am confortably off. As for working for a brewery or distillerry yeah certainly would especially if they gave out free samples.

Tobacco is legal so really it depends how you feel about it.If you think you are making personal gain through somoene elses misery then I guess you probably dont. If you view it as providing something that people want and enjoy then you probably can. But only do it if you are comfortable with it. If it dont feel right to you dont do it.