We do this - or did this - on St. Martin's day:
https://en.wikipedia.org/wiki/St._Martin%27s_DayBut while in the 90s and early 2000s at least a dozen kids came past our house each year, it's been dwindling to a handful at best. In the late 90s, i came home with a couple kilo of candy. I'm unsure about the reasons why fewer kids come to sing for candy. Perhaps they get enough already. I know we had a lot of cookies and chocolate at home because of where my father worked, but candy - not nearly as much. So i liked the opportunity to get all the wine gums, jawbreakers and gummies i could get my hands on.
That said, in the village where my brother lives, apparently people are now doing it for halloween, which kinda rubs me the wrong way. I don't dislike halloween or something, but i am somewhat annoyed by people who feel the need to americanize everything here.