I would expect to hear that argument but I don't believe it is correct. I can't lay my hands on the references now (my books are all boxed up) but I believe the cannon were privately owned. The powder was probably a mix of private and gov't. The powderhouses worked a bit like a bank. You could store your powder there retaining a chit to retrieve it as desired. It was safer that way as the old black powder was a bit unstable.
You can bet there was a surge in private stockpiling of ammo then just as there is now.
Agreed, and I think those actually were the arguments the radicals put forward. Don't get me wrong; I wasn't trying to argue the British case for the win, but merely trying to present it as it was.
And to agree that while it was, technically, a gun grab, it wasn't a gun grab in the sense we use the phrase today. It was nothing short of a strategic military move that backfired terribly.