First of all Atlanta and Charlotte have vibrant EDM scenes. Anyone whose ever partied there, or knows a thing or two about DJ culture knows that the crowds in those markets will definitely support a broad range of Dance genres.
Furtermore, All I see here is that you two brought up just one song, and try to pass that off as if Dance doesn't work in a certain region. Well, since we're on the subject of that song, in Nashville both 102.5 The Party and 107.5 The River are playing "Stereo Love".
It's Top 10 at 93.9 Kiss FM Raleigh, Top 10 at Hot 100.5 Norfolk, Top 20 at Channel 96-1 Charlotte, Top 5 at 95 SX Charleston, Top 20 at 99.7 DJX Louisville, Top 10 at K-Hits 96.5 Little Rock, Top 20 at K-92 Roanoke, Top 20 at Q-94 Richmond, Top 10 at Channel 104.9 Tri Cities (TN), Top 20 at 97.3 Kiss FM Savannah, number 12 at 94.5 KSMB Lafayette, Top 5 at 96.5 The Mountain Chattanooga, Top 20 at 107.3 The Q Columbus (Georgia), Top 15 at 107.1 The Monkey Biloxi, Top 15 at Hot 101.9 Fayetteville (Arkansas), Top 10 at HD 98.3 Augusta, etc.
Is Dance music as big in the South as it is in Miami, San Francisco, or New York? No, but Dance isn't too big in cities like Pittsburgh either.