I think you may have just not seen them yet. We had a Glenmary Missioner from Kentucky speak at our parish a few years ago about the need for outreach to them. He was particularly arrogant and condescending. One line from his whiny little homily was "Hispanic? Panic!" Glenmary was already off my contribution list due to the article in their magazine about posting sentries outside Masses attended by illegals, but he made sure they'd never get back on.
There are lots of formerly hillbilly towns in Tennessee that are now Mexican towns.