That was creepy.
Do you know the background of the people who did it? Obviously, they had a bad experience, too! It would be interesting to know where they are coming from.
Have you ever seen The Simpson's "Joy of Sect" episode? It makes a similar point...not quite as dark. At one point, Marge is trying to leave the sect they have joined and the loudspeaker is saying "You are free to leave". As Marge is trying to leave, she has to go over a barbed wire fence and a field of land mines as she hears the phrase repeated, "You are free to leave!"
Even 20 years later, that would creep me out. Pyschologically it would be accurate. There was the door, but how does one leave what is familiar to a post group existance. The only reality is the group itself. Good description.