Less than forty years ago, it was mandatory for foreign films that were distributed in Germany to adopt a German title. While this might seem fairly obvious to some, you would be surprised to see how many great movies have been lost in translation because the German title didn't quite capture the meaning of the original.
Surely, the cultural distinctions carry some of the onus for the unexpectedly wacky foreign titles - on one hand what might sound good to an English audience could seem absolutely lame to the German audience when translated and vice versa. The titles are set by the distribution companies involved who own the distribution rights in Germany and their decisions are largely based on marketing motives rather than good faith.
What's more, as time progressed, it became common practice to keep elements of the original title but include a German, often redundant subtitle; hence, the movie Scream became: Scream: Schrei! and so on.
But somewhere down the line, the people in charge must've deemed the mere addition of a German subtitle as lackluster and began treating audiences to an entirely different title (often with unintentionally hilarious results) which deviated from the original, such that most English speaking people wouldn't recognize it, even if it was translated back into English.