I justify it by thinking about how bullying is only 'good' when it's done against bullies. This person supports causes that 'bully' people in the world, directly or indirectly. Therefore, bullying this person is justified. Otherwise, I too am very anti-bully and feel it's probably one of the sentiments that is most broadly supported. It's just that people have fucked up notions of who's being bullied and who isn't.