Writer's Fallout Shelter

hey! im new, so be easy. anyway, i am a complete horror junkie. i love writing horror. but have you noticed that every single piece of writing that envolves horror is written along the same line as other horror pieces. i just want to know why is this. i mean look at romance for example, the main aim of writing romance is not always to show 2 people in love. so why in horror is the main aim to scare people. What if this is not the main aim? What if the main aim is to give the reader an insight to....another world. how do we know that the lines according to which we write horror is actually what horror was intended to be.?