I think AA just wanted the slots at Saint-Louis
Too bad, this airport is just finely located almost right on the middle of the continental US, much better located than DFW or even ORD for offering less than 3 hr long connecting flights to every part of the country.
-the service to Paris-CDG was not even assumed
As for US and CLT, they also offer connection to PHX/SAN/SFO and LAX. From CDG they serve CLT and PHL. There too, they make little advertising.
Alain