How would it be too "gamey" for them to finally institute transplantation of resources, a thing humans have been doing in the actual world for thousands of years?
I would like to see a mechanism for moving crop- and livestock-based resources to new locations. Restrictions would need to be put in place regarding, for example, the terrain you could move them to. And maybe there shouldn't be a guarantee that they would "take" in the place you attempted to put them. It wouldn't do to allow resources to become so ubiquitous no one ever needs to trade for them. But Madagascar vanilla, Indian tea, Caribbean sugar plantations, and the Wild West horse culture would not be possible if crops couldn't be replanted or livestock bred outside their native areas.