After recently re-watching the movie, there's a bit of a continuity error where his hair is short like that, then long again in another shot, then short again. I initially thought he cut it after his discussion with the secret service guy, so he wouldn't be as easily recognizable, but he actually has it short during their talk.
I saw someone saying they were going to give shades to the haired sculpt, but FYI he only wears the shades when he has the hair cropped close like that, or when he is wearing the mohawk.