Our society is so obsessed with things that are supernatural or fantasy type genre of stuff, you can tell how true this is with the popular movies, books, TV shows. The twilight movie series was one of the most popular series and to this day has a very devout cult following that is one of the strongest followings of all time. For our love with zombies you can see that from the extremely popular TV series "The Walking Dead" this is one of the most popular and most watched series on right now. There are twitter accounts for it fan accounts and nights when it is one people will always be posting on Facebook or twitter about what happens in the episode. You can see our obsession with ghosts with how many movies there are about ghost activity, paranormal activity, hauntings, exorcisms, etc. the paranormal activity series was extremely popular.
I think our obsession with this kind of stuff comes from our wonder of the unknown and things that we don't understand but want to very badly. Movie makers and TV show makers I think preyed on our fascination with this and maybe even a little bit of fear to get us to go watch the movies or tune into the tv series.