Parody Movies have a long tradition throughout movie history. They also have a tradition of not like by critics. Even Space Balls, a movie beloved by millions of fans was just given 2 1/2 stars by Roger Ebert. Getting 3 stars for a parody movie is recognized as an achievement and the last parody movie which had done so to my recollection was Scary Movie which received 3 stars by Roger Ebert. Naked Gun is recognized as almost a masterpiece at 3 1/2 stars.
My favorite parody movie as of late was Superhero Movie but that was not reviewed by Roger Ebert. I figured that the first Forty-five minutes were brilliant (particularly the spoof on Spider-man's origin) but the last part kind of abandoned spoofing movies and continued it's own plot. Tropic Thunder was a borderline parody movie and that received the achievement of 3 1/2 stars. It's borderline because not a large part from the movie was spoof material, it contained only small homages here and there.
I believe which may be where spoofs need to go in the future. Take a movie like Meet the Spartans. It essentially takes the movie 300 and adds gross out blue humor. The main reason the film am bad was that it based the jokes round the need to rigidly stick to the storyline of 300 instead of drawing from a larger source material and finding stuff that were funny.
Great spoofable moments in movies like "You Can't Handle the Truth", the death scene in Robocop 1, the twist after The Usual Suspects, Rosebud in Citizen Kane, the romance scene in From Here to Eternity, and Arnold moments happen to be spoofed numerous times and I never become ill of seeing them. If your movie is spoofable there are always new twists that can be put into create a new spoof from it original.
The issue that movies like Vampires Suck has is that it feels the need to pander towards the audience because it really wants to be considered a commercial success. It's attempting to take advantage of the prosperity of the twilight movies instead of trying to capitalize on the success of being funny. Pure parody movies need to find their success on videos where devoted fans can appreciate obscure references.
parody videos
The initial Austin Powers movies found the majority of it's success on video among fans who are able to appreciate references to movies that did not emerge 5 minutes ago. The other ones didn't achieve this well because they started to pander towards the audience.
Good pure spoof movies will need to go direct to video to allow them to be matched with fans who can appreciate subtlety. Movies using the odd spoof in some places like Tropic Thunder visit the big screen where less knowledgeable moviegoers can appreciate the film for it's own merits.