During WWII the Army had over 120,000 ships and watercraft. And even today it has quite a few large vessels.
Admittedly my own ignorance regarding the military is playing against me here. But, if there is a real life precedent for other branches of the US military other than the Navy to have and crew boats, than why are so many upset that the Air Force would crew a starship? In light of what I know now, it seems to me a logical extension of how things are in real life.
That being said, I still think it odd for there to be such a large Army presence on the Korolev, particularly among its bridge officers. For one thing, piloting a starship would probably a job they'd give to a really skilled pilot. Not to slam the Russian Army, but I would think you'd find more more qualified pilots in the Air Force than in the Army. But maybe I'm again out to lunch. My knowledge of military, Russian military at that isn't quite up to par.