that is INCORRECT.
As a former Marine and a current govt contractor that works on a Marine base I can tell you that Bases follow the state & Federal laws.
Back in the day you could drink beer & wine in NC if you were over 18 and hard liquor if you were over 21.
That rule no longer applies. Everyone has gone to a 21 yr old age limit for any alcohol.
Many Enlisted Clubs are closed and the whole Club system is shot because of this and the crackdown on drinking in the military.
EBUCK