You are right. They used to warn about coworkers inviting you out for a drink after work...which can lead to AIDS. Do not accept gifts from "worldlings" or buy used items at garage sales because these.items could be demonized....and then you'll have a demon problem in your house...the demons are known to fondle people in their sleep.
All these things are forms.of Isolation. Abusers.try to isolate their victims so that the victim is dependent upon them. (For example an abusive husband is very controlling and does not let his wife have friends.) This is how it is in this evil cult.