When my Dad was in the hospital for a hernia operation back in 1977 I remember visiting him. Smoking must have been allowed in public buildings then because people were smoking there. The man in the next room had lung cancer and had a hole in his throat (that little area at the bottom of your neck right before your chest). I was walking down the hall and looked in his room and saw him
smoking through that little hole!! 
OMGoodness......it freaked me out! It was the creepiest thing I have ever seen and I remember it vividly to this day.
I've never been addicted to cigarettes but for him to keep smoking during that period in his life it must be an extremely hard habit to break.