There is a lot of superstition in the world, not just among old people (and not just Koreans). The issue is most don't critically question the things they believe in. Especially when there are many others around them who say the same thing. Rationalists will always be contrarians.

The fan thing sounds silly, but it does make a lot of sense to look into more realistic ideas from the past or the present, even and maybe especially when the mainstream doesn't subscribe to them.