Why does Derrick and Danny allow Seth to talk to their sister like that?

That was really the only scene Seth had with his sister and Derek was busy talking on the phone, while I think Danny just felt that Seth was playing.

Because she is a worthless leftist brainwashed by her leftist college professors. She had it coming. There's only so much they could do.

Maybe they draw the line at physical. As long as it's words and not action, they don't care.

she was a democrat. arent democrats supposed to be ultra feministy and shit? why should they do anything about it? shes a strong independent woman who dont need no man.

Seth was a real punk.

Because they were friends with Seth. They knew it was just words. He wouldn’t go past that