Mxy, there are loads of movies out there with characters nobody has heard of before they go to watch it, and they are still huge sucesses. Nobody, or at least barely anybody had heard of Indiana Jones, Star Wars, Robocop or 1000s of other characters in movies, but they still went to see them because of good promotion of those films, and by your reckoning, word of mouth!
Lets face it, who the fuck knew Blade was even a Marvel comics character, but that didnt stop that film being a sucess!
But none of those ideas were directly attached to pre-existing concepts. For example, if you did an Indiana Jones movie NOW that he's well known, and didn't respect the main concept of the character, it'd bomb. It may get a strong opening weekend (simply for being Indiana Jones), but the negative word of mouth caused by angry viewers would kill it.
Make a movie with minor DC characters and call it "Super Team" and it may be a minor success or even a big hit. Make the exact same movie and call it "JLA", and the negative backlash for seemingly disrespecting its own premise will cause it to flop.
