It doesn't take a brain surgeon to see where some of those dislikes came from by just looking at the comments. Several Korean fans have commented about how ugly she is...Seriously?! Another fan states that Japanese people have an inferiority complex. What does that have to do with anything?!
That said, there are plenty of Korean fans who also said some nice comments, so I'm not saying ALL Korean fans are like this.
Lesson: Life is about balance. Have your apple pie, but also have your fruit salads and other vegetables too
I think here we can use the notion of antifan. Like, someone's professional hater))
Fans spend their time following a skater's career, going to competitions, watching the vids, reading interviews, discussing on boards, sometimes creating fanstuff like banners, fanarts, clips, etc. It's a pleasure to fill your time with your favourite skaters.
Yet some guys, I bet you saw them, for some reason find it smart to waste their time hating - obsessively post on boards how disgusting a skater is, argue with his/her fans (they may call it trolling), leave offensive comments at Youtube videos of this skater, of course dislike (I guess often without even watching). Or they search for doubtful statement in the interviews, and laugh that "oh look, she mixed up alpacas and llamas, she's so ignorant and stupid". Such people may take time and create some stuff to ridicule the one they hate, like take a bad fall pic and add some presumably funny caption, and so on.
Perhaps these activities make antifans happy, or they consider they make the world aware of what is, in their opinion, the real state of things. It's just the agressive human nature, yet I still sometimes stare at the comments like "her face is sooo ugly and her music choise is tasteless as usual" and it makes me wonder whether the one who wrote this is now proud and the day has not gone in vain for him.
But I think it's important to call a spade a spade. And using your analogy, I think its worth noting there is a bushel of apples, ie a pesky contingent of Korean fans who, for whatever reason, are splashing the YouTube video full of cruel comments.