It can be hard to adapt comics into movies, as there are some elements of one medium that aren't as easily acceptable in another: case in point the upcoming Captain America film. Instead of just throwing him out there wearing the red, white, and blue, the writers/director are going to have that be a costume he wears for USO shows in order to hopefully make it more realistic.

"The costume is a flag, but the way we're getting around that is we have Steve Rogers forced into the USO circuit. After he's made into this super-soldier, they decide they can't send him into combat and risk him getting killed. He's the only one and they can't make more. So they say, 'You're going to be in this USO show' and they give him a flag suit. He can't wait to get out of it."