Attacking People Over a Ship

I understand that many people defend their favorite ship as if it were a sports team, and I get that people may not like certain pairings or may even project themselves onto others. However, I don’t understand what people hope to achieve by attacking ships they don’t approve of or feel jealous of. Do they think that people will stop shipping, drawing fan art, or writing fanfiction because of it? I can’t see any purpose in making life difficult for shippers they disagree with.