We were talking at dinner last night about local speech patterns we have observed since moving to Missouri from California.
I have two major pet peeves in that area. First, and most annoying, is that it seems to be acceptable to use the wrong verb tense when speaking. I hear it every day and it takes a lot of restraint to keep from correcting people. The other is to pronounce the word "him" as "eem". So a sentence that, in simple English, means "I saw him" would be pronounced "I seen eem". It's also common to use the word done when did would be accurate (back to the verb tenses). "I done that yesterday." And nobody seems the least bit self-conscious or even aware of the error.
I know the local schools teach English, my son is enrolled in a local public high school. And people read and watch television and movies, so they presumably have exposure to correct usage.
I can say without a hint of sarcasm that these wide-spread habits baffle me.