Both my mother and her husband are smokers. They don't smoke because they want to kill themselves. As far as I know, neither one is suicidal. Rather, they smoke because it releases stress. It's a coping mechanism for them. My mom's husband is also a recovering alcoholic. As he's explained to me, he drank to drown out the pain. It was a coping mechanism for him. He'd get so drunk that he'd be oblivious to the world around him, he wouldn't feel the shame, regret, and pain that he often felt. He didn't do it to kill himself per say, he did it because he wanted an escape. He's recovering now though and finding different coping methods, I can only hope he and my mother will attempt to quit smoking soon as well.
People do dangerous things for different reasons. The above is just my mom and her husband's reasons. I can't speak for anyone else. No one can. I self-harm as a coping mechanism, but I also do it because I'm addicted to it and because it's a punishment of sorts. But those are just my reasons, not anyone else's. Another self-harmer may have an entirely different reason for their dangerous habits.
Everyone has their own reasons for doing something that they know will be dangerous for them. That's all I can tell you.
Smoking, alcohol, drugs, etc. are commonly used to obtain pleasure. But on the other hand, they can really be used to purposely harm yourself. So I think it fits into both, really.
I smoke on occasion. I assure you, I have absolutely no desire to kill myself.
People do dangerous things for different reasons. The above is just my mom and her husband's reasons. I can't speak for anyone else. No one can. I self-harm as a coping mechanism, but I also do it because I'm addicted to it and because it's a punishment of sorts. But those are just my reasons, not anyone else's. Another self-harmer may have an entirely different reason for their dangerous habits.
Everyone has their own reasons for doing something that they know will be dangerous for them. That's all I can tell you.