It is the mission of the USFSA to promote the sport of figure skating in the United States. Skate America is the second most prestigious event on the USFSA calendar, after U.S. Nationals.
It is not the job of the USFSA to promote the Cup of China -- that's the job of the Chinese federation.
The Grand Prix is a creation of the ISU. The interests of the USFSA may not always coincide with those of the ISU.