exactly as mmm says
movies are made for consumers, and that ultimately is truth for american mainstream movie producers.
producers don't want their consumers to become confused or disappointed, they don't need you even think about movie, they just need you watch it and pay for it. so they are not going to put too much things like german speaking cause a consumer could start argue about that, like it was not worth watching or something, cause they don't understand german. and it is same with other bits. like how the battles are performed. in a real war you would shit bricks should you go fight in a first line. but in movie it is not possible to make it real-alike so they just put few bangs in there, ppl operating some consoles, ppl taking radio calls, and then again some bangs, some shooting and so it looks heavy, it just cannot look boring.
and don't worry about the ppl in a movie, if you watch a movie of foreign production you certainly won't see americans in there
the missiles
how much do you think a single shot costs?
about a million?
just in case you wanted to think about it as a real world scenario.