I don't think it was just the military. I think lots of civilian stuff of the era in which these were designed did the same thing.
Suggestion based on personal preference- Instead of powering the front markers from the headlights, rob your power from the tail light circuit. No extra switches, you can still choose parking lights only, or headlights and parking lights, except all parking lights remain on if any are on, very much like a modern pickup. Good post that Recovery4X4 linked to, there are lots of others as well.
I have my wires marked for this modification... Knock on wood I havn't been called on it yet, but while the ticket may stand they can't deem it unsafe and haul it away over lights (even at night) if it's "fixed" before the tow truck arrives...