Just how does that follow?
Does the First Amendment allow for licensing of newspapers?
It doesn't even allow special taxes on newsprint or ink. Only as part of a tax on some larger category of items can these be taxed.
Now the ammo tax was originally pushed by the hunters, but then Billy Jeff started using the money for taking land out of hunting and to directly benefit non-game species. It was illegal, of course, but that never stopped BJ from doing much of anything.