I remember when I was a kid all the restaurants had ashtrays on the table. Even McDonalds and Burger King had little aluminum ashtrays on the tables. You could have your cheeseburgers with a side of secondhand smoke.
When I worked (as a cadet) on a chemical tanker, there was a designated room for smoking, because smoking anywhere else, including the deck, is forbidden due to possibility of fumes. So during coffee time (in other words, any break) everybody would gather in the smoking room, regardless of their smoking habits (cause otherwise you'd likely be alone). And as someone who hadn't dealt with cigarette smoke up until then, I still got used to it rather fast, in a couple days or a week. Still don't smoke though.