The hearing protection is just a part of the times. Hearing protection was not used back in the day. I could be remembering wrong, but when I was in boot camp, in 1971, when we shot on the range, I do not recall us using hearing protection. That is why so many of us old farts are hard of hearing.
If you want to see TV episodes that are full of firearms errors, watch some of the British crime dramas. In one episode they were talking about the 9MM as being a very rare caliber for a handgun. They will be talking about someone shooting an automatic, and show a picture of a Webley. I also learned, watching Brits crime dramas that the British have very thin skulls. A thump on the head that would make Jim Rockford wince and feel for the knot on his head, is nearly always fatal on the shows.