yeah its because of the zoom extent on the map itself. Pitt shows in view and either they give Pitt a generic color based on how they drew the rest of the map, or they don't give it a color at all and you get weird polygon edges where you decided to stop the colors as I am sure you can't just blend the edge to become nothing.
Seems like a silly thing to argue over (not you), Its just a nature of the extent at which the map it set to.