I know there are many people who are interested in these anonymous markets, and Crypto currencies who are also not going to be selling or buying drugs. Why don't we work on setting up a market but for legal products. There are many people with bitcoins, light coins and many other currencies that don't want to buy meth but would love to buy a blender, or a duvet cover, a part to their jeep, ext... I would love to help make that a thing we could do.
There are clearnet sites like Bitcoinin.com where you can buy all kinds of legal things with bitcoin. I just received a couple of books I bought from them the other day.
To answer your question, a market that sells totally legal things has no reason to be in the dark net.