Jonah: Sale of explosives was not heavily regulated in all states at least into the 1970s. In the 1973 movie Charlie Varick, Walter Matthau goes to a store and buys a couple of boxes of dynamite. As he’s heading out the door with the boxes in his arms, the clerk calls out: “May I ask what you need it for?” Matthau, not breaking stride: “Sure, you may ask.” Exit.