I am not sure when promiscuous smoking became acceptable — 1920s I think. Prior to that, smokers were segregated off to special rooms & places. Calvin Coolidge’s wife, just like mine 100 years later, made him go outside to smoke his cigars. Yet in the 1950s, everybody smoked everywhere. When I started riding the London Underground (=subway) in 1963, one carriage in four was designated for non-smokers. A fug of tobacco smoke everywhere had somehow become the norm. I saw my first few hundred movies through a veil of tobacco smoke rising from the movie seats in front.