I can't advise on US federal or state laws but I can tell you the basic principle involved, which is the same all over the world.
Governments make money out of alcohol that is consumed (undenatured) by levying duties and taxes on it. To protect that income Governments require alcohol that isn't intended for consumption be 'denatured' which usually involves having something poisonous and something foul-tasting added to it so that it is no longer potable. What that means is that denatured alcohol is then vastly cheaper - that's it's only advantage for making perfume.
In the UK no license is required to sell perfumes made either way, and you can buy as much alchohol as you like as long as you pay the duty on it. If however you want to buy denatured ethanol as such, you have to have a license from HMRC (though there are ways round that by buying Perfumers Alcohol or the like, which has other things added to it so that HMRC don't class it as ethanol but as a finished product).