Ya know since when is calling somebody a flatlander "derogatory"? Please, what is with everyone these days having such thin skin? Next thing you know it's going to be considered a racial. Boy I tell ya the lengths to which some take the political correctness is beyond ridiculous.
Hell people call me a redneck all the time and frankly I'm damn proud of it too. If some use that label in an attempt to make it derogatory, well that's their problem, not mine. Afterall they are no doubt a flatlander.