Back when radio was much, much bigger than it is today (sorry, Rob), if you were releasing a film of any kind, you were faced with a dilemma. A huge arena for promoting your film was radio--but how do you promote something that's primarily a visual experience with just audio? Especially if you've got a horror movie coming out--which is, genre-wise, even more visual than most? Answer: you do a radio spot. And you do it...badly.
Let's look at some examples. First up, The Amityville Horror from 1979...a few from this film. One thing you'll notice in all of these is a great deal of repetition. That's if you have something worth repeating. And "Get Out!" is definitely worth repeating. But that's a more...mainstream, respectable sort of horror film. The sort of radio spots I adore are ones like this for Werewolves on Wheels from 1971.