I think it's more the surrounding culture than the fandom itself; like, in Korea they have a ton of 'variety shows' that idols can appear on, so fans can see their idols doing all kinds of things on the shows (running obstacle courses, cooking, learning a new style of dance, taking care of kids, and [very very frequently] doing dumb games and acting like giant lovable dorks.) I think for a lot of kpop fans the appeal is in the juxtaposition of the very polished, cool appearance of idols on stage and their dumb 'natural' appearance on variety shows.