The other day while pointing out how two game boxes looked quite a bit alike, a friend mentioned that there is an entire site devoted to repeated movie posters. After a little digging I found the site. It's in French, but you can look at the images and get the idea.
http://christophecourtois.blogspot.com/search/label/cin%C3%A9ma
Here is one of the examples off of the page:
Now, I do agree that these all look the same, but I'm wondering the reason. People like things they are comfortable with. People like repetition. Just look at any of the reality shows that are popular now or sitcoms that were popular back in the day. They are all the same thing over and over.
Now, the question is, is it the designer, the creative director, or the studio?
Studios are notoriously known for not wanting to take chances. Using repetition is safe. If it worked once, it can work again. Creative directors, while boring at times, would usually push the idea a little farther. The graphic designers probably have very little say in the matter. So, I'm going to go with blaming the studio. That's a pretty easy out, but it's probably the truth.
The last option, which is tempting as well, is that it has all bee done. There are so many movies made each year that there is no possible way to create an original poster. A designer could spend years looking through archives trying to make sure his or her work is unique only to find out that the exact same idea was used in a French poster from the 70's.
So the question is, are there any original designs left?