Today I was reading a psychological book about love when I found a fascinating description about a kind of love called "Idolatrous Love". Which I think fits into a lot of people who likes this hobby, and it says, "If a person has not reached the level corresponding to a sense of identity, of selfhood, rooted in the productive unfolding of his own powers, he/she tends to “idolize” the loved one. He/She is alienated from his/her own powers and projects them onto the beloved person, whom he/she worships as the summum bonum, the bearer of all love, all light and all bliss. In the process, he/she deprives himself/herself of all sense of strength, he/she loses himself/herself in the beloved, instead of finding himself/herself."
The idolized or beloved person, in this case a k-pop group or an idol, and the description of their love is a great way to explain why we would see the kind of dedication and emotional force some fans convey.