You mean they all don’t talk like harry reid?
Some do & some don't. Dealers there come from all over the world. Las Vegas also draws gamblers from the whole world. Dealers are exposed to the dialect quirks of the entire US & "where are you from?" is common chit chat. Dialects are regional, more than they are state by state. The closer you are to home, the less you're going to notice differences. They might be able to get more specific if you stay at their table longer, but I said 5 minutes, which is enough time to get the region right.