I find it funny and witty. To me it's poking fun at door to door salesmen of old, and our lessend acceptance of gun ownership. I think it's a very subtle humor, and that's why not everyone gets it, but I also think the subtlety of it makes it even funnier. It also presents me with an image of my personal utopian society. A place where gun ownership is so commonplace, so accepted, and so un-legislated, that compaines could viably use this method of marketing to the masses.
don't forget, humor is in the eye of the beholder.