That is not the only warning film not to do it because people were dying all the time: https://archive.org/details/more_dangerous_then_dynamite
Some headlines of people making the worst mistake of their shortened lives:
https://www.newspapers.com/article/wilkes-barre-times-leader-explosion-caus/13045180/
https://post-gazette.newspapers.com/article/the-pittsburgh-press-gasoline-caused-two/91356754/
Occasionally, they got lucky and survived.
https://www.newspapers.com/article/hot-springs-weekly-star-cleaning-clothes/124927252/
https://www.spokesman.com/stories/2017/aug/29/100-years-ago-today-in-spokane-woman-using-gasolin/
I’m reminded of one of those detergent commercials where the stock housewife character takes the freshly laundered snuggle blanket and hold it up to her face and inhales deeply to enjoy that fresh scent… Only now because of this information they subsequently pass out from the gas fumes lol