If a corporation's main goal is to increase revenue, but their only customer is the military, why is it that we would force the rules of stock markets on them? Military R&D isn't something you can sum up in a quarterly report, nor is it something you can tack KPIs onto on a regular basis - some of that R&D is classified.
Plus, thorough lobbying, it basically forces our military to be in wartime 100% of the time, because contractors cannot have a bad quarter, so they need to constantly have new theaters to sell into, which in turn forces the DoD's hand (and don't get me wrong, all the DoD employees probably own Lockheed stock).
Why contractors are allowed to lobby is beyond my comprehension.