The movie is entertaining but bears absolutely no resemblance whatsoever to hillbillies I grew up with. Behaving the way he does, the father character would have been shot dead in his teenage years where I come from in West Virginia. A brutal thug like him would never have fathered any children if he did survive because no woman would ever have married him.
In the hillbilly culture where I come from, the family group is typically one of matriarchy. As for the father selecting his daughter's husband, that is totally and completely ludicrous. In the hillbilly culture I grew up in, father's will typically object strenuously to their daughter's selection of a mate but that's only because he doesn't want her to leave the house.
As for the doctoring there, most people don't go to doctors or dentists. The hillbilly medical practice goes like this: you ignore the pain until it either goes away or gets so bad you can't stand it and you have to go see a doctor. If it goes away, which it usually does, then you didn't need a doctor anyway. If it gets so bad you can't stand it then maybe it's something serious or maybe it's something you can live with. Dental practice goes like this: you never do anything to your teeth until the cavities get so bad you can't stand the pain. Then you go to the dentist, get them pulled and get false teeth.
Personally speaking, I never brushed my teeth until I joined the Navy in 1963! I never took a shower either! Needless to say, those bad practices and habits were quickly altered in boot camp.