I think the Plath kids were allowed to socialize, but only with like-minded families and only with adults present at all times to supervise. Personally, I wanted my children to be exposed to people who were different (religion, race, beliefs, etc.) because that's what makes up the world and they need to learn how to get along with everyone. Of course, there were plenty of discussions about why we didn't share some of those beliefs. The main job of parents is to raise children who can live independently and think for themselves.