Col, you left out one part, at least relevant to the first Tremors. All the women look like Reba McIntyre.
Of course, the reality is slightly different. At least one of those weapons would not be allowed. The survivalist refers to his "cannon" as the reason he had supplies of the black powder they used to make the pipe bombs. In fact, civilians are not allowed to own functional cannons. The other weapons? None of them were demonstrated as being fully automatic, so the rest of the lot was probably OK, including the elephant gun.