That's because you have the $80 to spend on just a little bit of ammunition. People who could afford only the lower prices, simply can't spend that kind of money on ammunition. All that high priced stuff will still go to hoarders who can afford to spend a lot for it.
Us poor people can't do that. We might be able to catch up with the occasional box at a lower price but the expensive stuff is out of reach, even if it is on the shelf.