There is a lot of sexual innuendo in Paper Moon, now that Bogdanovich pointed out the whole Trixie Delight sabotage by Addie. I now see it in nearly every scene. Now that I see it everywhere, I was a chump. I have always been a chump when it comes to these things with women. 

The movie was based on the book, Addie Pray, which was written by a southerner and set in the South. The shooting locale changed to the Midwest upon Polly Platt's discovery of "the road", the setting for the car ride scenes. The screenplay did not make it. Alvin Sargent's script has references to Dixie Bible Company out of Biloxi. Even in the movie script, Imogene says she is from Troy (Alabama) and tried to push Trixie out a window in Little Rock (Arkansas). The accents are a little too southern to me, but I don't know the Midwestern accent, if there is one. The diction likewise. "Anybody t'home?" Maybe the accent and diction were common to the poor regardless of region.

I can easily see underage sex, even incest, occurring in the South, but in the Midwest? I don't have the same impression of these matters in the Plains states. But it is all over the book adaptation.