it feels like zombie movies aren’t allowed to take place in a world where zombie fiction exists, because when characters are pointing at the walking dead and going “oh hey it's the walking dead like in the hit tv show The Walking Dead” it really lowers the tension
conversely werewolf movies are encouraged to take place in a world where werewolf fiction exists, because when someone's been reading up on lycanthropy and later they find themselves getting all shaggy and toothy and stuff, they know how bad things’re about to be for them and everyone else around them
we watched The Slender Man recently and there is a scene where a character consults the Slender Man Wiki to figure out what they’re dealing with