In one of the Space marine cinematics, I think it was the first one actually. There's some tactical marines jumping off a thunderhawk, one of those space marines is depicted as having a white helmet showing he's part of the honour guard. I never see these guys in game however and they only show up in this cinematic, why is that? It would've been really cool to have those guys in the campaign or something.
Why even bother putting them in the cinematic if they're not going to be used or even mentioned directly?