There's certainly a history of big tobacco getting actors to smoke on screen, so that's certainly part of it. But another reason an actor might want to smoke is it gives them a way to utilize body language in a way that's plausible within the scene. Cigarettes, cigars, pipes, pens, eye glasses.. these sorts of props are often almost invisible (as the audience just sort of takes them for granted), but can be used by an actor with intent to convey some unsaid context.
Schindler's List. Saw plenty of scary movies before this, but that scene where the officer murders the engineering prisoner who's just trying to tell him about a problem with the building. It just sticks in my mind to this day as maybe the first time my young, sheltered self had been confronted with a realistic example of what dehumanizing could do.
Hats are the billboards of cultural status. A shiny metal hat bedazzled with stolen rocks of other cultures? Well that just advertises, "I've got a nice big army to make up for my small perspective".
There's certainly a history of big tobacco getting actors to smoke on screen, so that's certainly part of it. But another reason an actor might want to smoke is it gives them a way to utilize body language in a way that's plausible within the scene. Cigarettes, cigars, pipes, pens, eye glasses.. these sorts of props are often almost invisible (as the audience just sort of takes them for granted), but can be used by an actor with intent to convey some unsaid context.