I call hijinx on that map. Nowhere in eastern NC will you hear soda go by the generic "coke" name. It's Pepsi or else it's a fight you're wanting.
Birthplace of Pepsi
The stadium at ECU is named after a Pepsi distributor. In the 252, restaurants that sell coke are considered treasonous cavaliers.
My 30 years in the rest of the south leads me to believe that the most accepted term is simply, "drink". As in, "while you're up, can you get me some drink?"