Randy why is it a good thing that players can thumb their nose at the whole effort of placing oneself in harms way and dictate the outcome of so many who are willing to take that risk? This game is not a WW2 simulation, it's a combat simulation using WW2 toys.
I've run resupply during hot capture battles and the risk is very slight based against any other combat activities I've taken part in over the last 15 years. It's tougher to run troops since they give themselves away once you kick them out. I stopped running supplies to the town because one thing stayed constant for years, when you beat the attack with supplies, you often didn't see anymore combat for a long time that evening. In some ways delivering supplies to crap on all the players friend and foe who just fought over the real-estate is quasi the c word. The defenders only sense of it is now they have to wait for maybe the next fight to get started, if it even does for that evening.
Since troops in WW2 never had a giant red "P" hovering over them, why not base supplies stay persistent for 30-60sec with an icon and they can be destroyed during the persistent period? Some guys might even stay put to fight for their supply box with their 50cal.
Most of the players defending one guy hiding in the bushes controlling the outcome of 10-20 guys risking something by fighting have not been around very long. M3's with supplies screwing 20 guys is pretty much like handing out participation trophy's and dictating equal outcomes to make everyone a winner. The unintended consequence is how this stops a large scale activity for everyone involved on both sides with only one guy who pushed a single button sort of a winner.
Another possibility, when that box dictates the outcome of the base capture and ends the fun for both sides, a name in lights message should go up, player x just screwed your evening with his supply drop at field xyz. Everyone else gets a name in lights for combat deeds, why not name in lights for screwing people out of their evenings fun.....