The thing is other movies have proven you don't always need a huge origin story that takes up half the movie. Lord of the Rings: Fellowship of the Ring got the prologue out of the way quickly and pretty much jumped into the story. And it was hugely successful, even with people who had never read the books.
Wrath of Khan was the most popular Trek film with non-Trekkies and it definitely doesn't have an origin story. Bottom line it comes down to the writing and how quickly you can set up a situation and get people interested.
Yeah, but those aren't Super Hero films. The origin of Star Trek everyone knows, even non-Trekkies, because it was the opening narration of the old series, and that's been referenced and parodies to death.
There will, some day, be a Super Hero movie that isn't a sequel that takes you right into the action. I'm not sure if I should count The Avengers, since it did have the origins of them coming together as a group... and, uh... I didn't get to see Thor before hand, so I was slightly confused, but not totally lost. Even the first TMNT movie had the origin, but told the right way, a brief flashback narrated by Splinter. Even in the last film, that was taken care of with a quick narration as well.
But, if done right, there are dramatic character establishing and building moments in the origin story. That's what I liked about both Spider-Man film series. Sure, they had the info dump everyone knows, but they added much needed character build up with Peter Parker.
But I repeat... I would rather see an origin of something told a million times than lengthy sequences of the hero screwing around with his newly discovered powers. That's getting old faster.