Cinema Blend spoke with director Joe Russo, and got the following:
To talk a bit about Cap’s costume, it’s gone through two big changes from what it looked like in The First Avenger to The Avengers. So how much is it changing in this film. Does it have a kind of natural evolution?
Joe Russo: Yeah, I mean I think it’s on the floor [see the picture above].
The new one? Oh, that’s awesome.
Joe Russo: So, it’s out there, but for us, it was, it’s thematic for the film, you know. You’ll see when you see the movie what he’s doing and who he’s working for in the beginning of the film, that costume is appropriate for what they’re asking him to do. It is a stealth outfit. It is for secret missions and I think that, you know, it’s thematic. You know, you read online, people get wrankled when you, you know, mess with the stars and the stripes, but there’s a very specific reason we did it in this film. We won’t talk about the other outfits that appear in the movie, which you’ll see in the movie, but again, I’ll just say, that the use of the costume in this film has a very thematic arc to it and hopefully a very arousing arc.