The only times I've used 24 frame rolls was when I ran low on film in some out-of-the-world place - I'm born in the early sixties, so I'm not part of the generation any more for which using 24 frame film was a economising habit...
It has not been particularly popular in Germany ever since I can remember. I've mostly encountered it in very pedestrian consumer places - rural supermarkets, souvenir kiosks and the like, even places catering for photo amateurs rarely had it.
In the past twenty years, much of its former market has been taken over by disposables, so it is even more exotic today.