Hollywood's cluelessness about Southerners and soldiers

First, there are the terrible southern accents made obvious here in Plano, TX where the Dynasty filming at Southfork Ranch took place. There were local hands working on the set who were distinguished by genuine Texas accents that came from a different planet than the Hollywood efforts of "Californians" trying to appear "Texan." As a California transplant, it is all too obvious to me.
Ever notice shows taking place in Los Angeles where the characters drive out of town? The small country town where they finally stop is populated by people with "southern" accents, especially the hick sheriff; the only decent, intelligent person is the beautiful waitress working at the local cafe. ( If I may digress, notice movies where Californians stay among the Amish and teach them how to dress stylishly and more, well...California-ish?)

That said, on to the military portrayals:
Notice the soldier or Marine coming home from deployment: his hair is uncut and the uniform is grossly unmilitary. The most obvious item to me is the headgear being worn, or "cover" as Marines call it. Notice the cover being worn by the actor looks like this:

Unknown to Hollywood apparently, Marines wear their covers looking like this:

The filming of "Rocket's Red Glare" on the installation where I worked was interesting as well. Two of our Air Force women were used as extras for about five seconds (their scene eventually cut!) but for that, their normally closely worn hair was redone and increased liberally in size, looking most nonmilitary, but very Hollywood. The Tunnel Dweller