There's a few people that will deliberately portray a particular accent too, for effect. There's a classic little cartoon from many years ago that I think you'd appreciate called Cane Toad. I don't think I can post the link here but I can PM you if you can't find it.I don't know about that. Have you ever heard educated people from Boston, Massachusetts speak?!
That video is a classic example of a "put on" accent.