Seems like consolidated stockpiles of weapons would make for easy targets of destruction if there was to be a type of civil conflict. Plus if there is a civil conflict, guerrilla warfare is a huge strategic capability for the side that doesn’t have all of the money and technology to utilize. Having to go check out guns at a local municipality not only puts that strategy at risk during the checkout period, but I would imagine surveillance technology would then quickly identify “dissidents” and allow the federal government to target those dissidents quickly and easily.