Some valuable plants ARE tricky to grow: think about the fuss needed to start a coffee, cocoa, or vanilla farm. Macadamia trees need at least 8-12 years before producing nuts, and their quality's sketchy until they're fully mature.

I wonder if the early biotech scientists caved to concerns about GMOs, and said, "OK, if you organic farmers are worried about cross pollination from GMOs, and you corporate farmers are worried about loss of product, let's make a plant that only grows RIGHT HERE."