It helped one stay awake on night duty, and it was so much the done thing that to refuse a proffered fag was tantamount to refusing to shake a proffered hand. To smoke was doggedly seen (anyway by the youngest of us) as risque rather than risky, and being a non-smoker was priggish.
Every public space reeked of smoke. Characters in films, books and advertisements (not only those plugging tobacco products) had their interest and glamour enhanced by the way they handled the weed. Jewelled lighters and cases were a first choice as birthday and Christmas presents.
To fasten all blame on the tobacco companies is to evade responsibilities more widely shared.