Smoking is a very bad habit.
A bad habit is forgetting to lower the seat for your SO after peeing or leaving the milk outside the fridge when you use it. Smoking is an addiction with same mental weakness as you find with heroin or crack addicts. Similar to other drug addicts, they are defensive about their addiction and tend to hang around with other addicts rather than face the embarrassment and possible ridicule of their weakness from non-addicts.
Unfortunately unlike your heron or crack addict, engaging in smoking poisons the air that nearby people must breath. Faced with curtailing their habit or poisoning their own family, many of these pathetic addicts chose the habit.
It should be no surprise that people with a nicotine addiction tend to be more prevalent in the uneducated and lower social classes. I have found beautiful women who did not smoke. I suggest that you am a little higher in the class of girl you want to date.