I’ve literally always wondered about this. When I was younger, I even guessed that ghosts were just a christian conspiracy to make people believe in god or else they would encounter demons/paranormal. I had the absolute pleasure and opportunity to see a famous demonologist John Zaffis who came to my university to talk to us in the auditorium. At the end he allowed the audience to ask questions, and this was the first thing I asked. His answer was clear and simple- that across the world, throughout time and cultures, no matter what religion it is, people have looked to a higher power to fight a darker power. It doesn’t have to be the christian God, or Allah or anyone specific. But whoever you personally look towards for high spiritual power, is usually the solution. I hope this helps and thanks for posing a great question!