I’m going full tin foil on this. I took a flight from Philly to KC via Charlotte NC, Spring 2012. The Ph- CH leg was 90% black( African-American, African, Jamaican, who knows); the Ch-KC leg was all white. One could easily imagine a strategy by Obama to rent a lot of apartments in Charlotte to insure victory in a swing state, especially as the Democrats had targeted NC by even having their convention there. It was only one flight, but remarkable; I was never on that route before or since, maybe it’s always that way for all I know.
No tinfoil hat required...ask most workers in the Charlotte Airport where they are from. Almost every one of them is from Boston, NYC, Philly, etc. HUD in action!