Dream on. They'll just come up with more "creative" methods and more toxic ingredients to achieve the same results. Eventually the WOD will be stepped up to prevent ordinary citizens from obtaining such common household items as bleach and aspirin because somebody might invent a way to use them to manufacture meth, or some equally "evil" substance.
The problem with your idea is that ephedrine hydrochloride or pseudoephedrine hydrochloride is *the* critical ingredient for making meth. The only other chemicals you can make it from are phenylacetone and methylamine, which are highly regulated, highly restricted (forget about finding it in a local store) and pretty much unavailable to the common thief. There *isn't* anything else to make meth with.