That's part of the point. They thought he was crazy because of some mildly off behavior without ever considering how beep up their own motives were. This is what comes out when the one kid learns about the other's father. Characterizing him as 'psycho' was always an obviously exaggerated notion, contrasting with their claims of 'objectivity'. "We're going to objectively observe this psycho wife-beating drunk for six weeks." - it's MEANT to tip us off that they're hypocrites.