Being somewhat of a traveled guy, I noticed something I hadn't noticed before in previous showings of the film. First, the scenes that were shot when they presumably lived in Custer could not have been actually filmed in Washington State. I could tell right off the bat that the foliage, trees, and landscape is not typical for the area. If I didn't know any better I would have guessed they actually filmed the entire movie in different parts of the Appalachian mountains. A quick Google search revealed I was correct!
In fact, most of the movie was shot in far eastern Kentucky and southwest Virginia, the Webb's family homestead was actually filmed not far from where we used to live.

This is NOT a PNW landscape...
There is another anomaly I picked up on in the movie that seems a little far fetched.
When Loretta's singing starts to gain traction, Oliver "Mooney" (her husband) is seen skipping a nights sleep as he pulls an all-nighter on the typewritter. He goes in to work anyway. When Loretta offers to make him some breakfast he refuses saying he doesn't have the time, adding that when he gets home they have a gig in Spokane to get to that night.
Spokane??
Hardly. I googled that distance, and even in the modern era, that's at least a five hour drive. I can imagine how long it would have take during the time this was said to have taken place, which I imagine would have been a few decades before the completion of the I90.
Still a good movie though.