Anybody can order wholesale and some have. The real reason IMHO is that professionals like having exclusives.As even the Chinese could order wholesale and do whatever they want with them. DWN would not admit that, but I have no doubt about it.
It never works! In Africa armed guards surround the Peppadew peppers, yet I still grow them in my backyard.
Some companies that make their own cultivars have been able to keep them from leaking. Huntz, some of their tomatoes leaked, But other companies like the berry seller Driscoll have their own cultivars, and I have never seen them.