Having been a smoker for a while, lighters are less “stolen” and more “accidentally gifted.” If you’re with someone you know well you’ll be more likely to just pocket the lighter out of habit because you’re comfortable with them. If it’s a stranger you’d feel an obligation to get it back, or even have them light the cigarette for you.

If you know the person they might ask for it back, or they might let you keep it depending on how close you are with them.