It's the fans that are cancerous. They cause self-harm and cut themselves simply because a band member left a band.I saw one picture where a one directioner cutt of the head of their dog saying "This is what happens when zyn leaves one direction".

Boy bands typically cater to the younger audience, so they equally receive distaste from older audiences who do not resonate with that genre as well as youth who try to associate with more "adult" type music.