There are commonly state/country laws against collecting and removing natural fauna including berries and seeds. Once removed, there are international laws, like CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora), that may be applicable outside the country of origin if the plant is designated as threatened, endangered, etc. I suspect this combination has the effect of slowing/quieting trade in more newly discovered varieties, even once they've been removed from the source country.