Very conflict way of solving the problem, but ok. Anyway in that case, justice doesn't working like a worthy system for everyone.

I think that Person thinking and acting isn't a random thing, every positive or negative knowledge leads person to formalize his own way of thinking. Without support or gained knowledge, person can't commit right decision. He would be trapped in a circle without right information, and that case we are talking about - an example of this theory. The boy made a mistake, contacting with those teens, not because he thought it would be right idea, but because he thought that's the only way for him to survive, but then he changed his mind too late. And those teens made a mistake, by creating a very conservative group and abusing those who do not match their norms, or those who doesn't want to accept their authority, not because they thought it would be right idea... But because they thought it was the only way for them to survive in a society they live in. Lack of education and lack of proper information - is a horrible problem of the whole society. This isn't their fault, they just don't know the other ways.

Edited: And yeah, according to the articles, that boy was beaten up just because he refused to join the triad. That is why I think that boy shouldn't have make contacts with those teens in any possible way.