I found this little tidbit of information on the web:
"Anti-seize is designed to prevent galling or corrosion from locking threaded parts together. BTW, do not use copper based anti-seize on aluminum parts going into saltwater like on marine applications. It sets up a galvanic reaction that is almost as good as a weld at locking the parts together - use marine grease instead. So Grease can be used in the place of anti-seize, but not visa-versa."
It would appear that grease is indeed the better lube for freewheel to hub threads.