Imagination is our most precious gift. It is our primary vehicle of perception. So if someone believes that demons are everywhere out to influence them at every turn, then in all likelihood they will meet their demons in real time. There have been cases of people who were found frightened to death with no visible evidence of why they died in fear.
Buddhists believe that waking life is actually a dream state and that what we call the dream state is true reality. The Aborigines of Australia believe in the Dream Time as being more relevant than waking reality. There are many other cultures that have bizarre beliefs, at least in our perspective of things but they are just as valid and real to them as what we believe. There is no diffinitive way to judge who is right or wrong. We can only base our judgments on our own personal experiences and beliefs. To me, reality is subjective (metaphysical) and to the next it is objective (scientific). All are right to the beholder.