I think the rule is that if the base's land is owned outright by the Fed Gov't, then federal laws apply. If the land is leased from the state, then they obey state laws. Heard a "back in the day" story once about some good ol' boy sheriff in Miss-Hippy who tried to shut down the Meridian package store for selling booze on Sunday.
In any case, this isn't a case of local laws not being applied or federal laws being defied. There is absolutely NO justification for trying to enact a ban like this beyond the personal moral objections of a few. I don't give a damn if Rev Bob or Conrgessman Whoever don't like naked women. They can tell congregations and consituents not to buy it, feel free to quiver with righteous indignation at 1500 quivers/sec, do what they like, but DO NOT push your moral judgements on us or use the military as the hobby horse for your personal crusades.
If they have no justification for banning the mild soft-core magazines like Playboy beyond moral objections, then they are blatantly defying the seperation of church and state. If it's not religious and merely a personal distaste, I still can't find any reason why your definition of good taste should be enforced against the entire Department of Defense.
Did I mention this crap aggravates me to no end?
And by the way, I don't read it for the articles, I read it for the pictures of gorgeous naked women! So there!!!