As the quality in the movies games etc. keeps declining, so will the appetite for them. Eel, you're old enough to remember the onslaught of post-Star Wars sci-fi movies, whose VHS boxes littered the landscape at your local video store. Zombie flicks are especially long lived, just because of the ability to make one with very little money.
Not trying to lay blame at your feet, but I find it's easier to be less annoyed by a product over-saturation, by simply not watching, buying or renting the stuff after it overstays it's welcome.