Let's say you're a businessperson living in ancient wulin. You want to make money by starting some kind of business that caters to wulin people. What kind of business would you open?
I think I'd open a print shop and start printing up copies of martial arts manuals. People like West Poison Au Yeung Fung and Dong Fong But Bai would never need to kill anybody again trying to steal the 9 Yum Jen Ging or the Qwai Fa Bo Deen. They could just get copies of the book from my print shop.