I would not necessarily say dumb, but rather misguided or uninformed. I by no means support it, but if a child is raised by two parents who smoke everyday, I can see how they would think smoking is ok.
Its dumb. I can tell you this because Ive been smoking since I was 12. And its sooo hard to quit. Even knowing that its harming my health and I may die young. Quiting smoking is as hard or harder than quitting heroin. My advice to you is to never pick the habit up.
When I see a beautiful woman, and then see that she is smoking, it is an immediate turn off. It is absolutely the least sexy thing a woman can possibly do in my estimation. All I can think about is her breath, the way her clothes must smell, and the fact that she will look old before her time if she doesn't stop. And I used to be a smoker who dated smokers. Nothing like kicking the habit to make you go the opposite way.
As an ex-smoker, I say dumb. The addiction to cigarettes is hard to beat but you get so many bonuses with it, the ability to breathe without coughing, the ability to walk more than 100 feet without gasping for air. The ability to smell things, the ability to taste things...