For awhile, some meth cooks were using herbal products to get ephedrine - they (mostly) all gave it up, because it's too damn much work and there's so little ephedrine to get out.

Restrictions on herbal products are the responsibility of the FDA, not the DEA. Mostly, the FDA has its hands full trying to get people to back off on ridiculous claims of how their particular brand of snake oil will cure you of anything and everything under the sun. (I believe P.T. Barnum had an applicable expression on that one, too, the one about one being born every minute....)