Not sure why they are doing it specifically. With that being said I can think of a reason one might do this, not saying it's their reason.
Example : If I want to sell pink double daylilies for instance I might use a non-registered name so that if I ran out I could just send any old pink double daylily, since it is not a Registered internationally recognized name. The idea being that once you claim to be selling Dublin Elaine(as an example) you are expected to be only selling dublin elaine as dublin elaine. Truness to name could be challenged since it is a registered daylily, registered with the group responsible for international naming. Do you see how this practice might make a certain sense, for someone perhaps in the business of business and not named daylilies. It would be shady at best to do so, but possible to dupe the unsuspecting public, who may or may not know there is a registration system set up.
Just my 2 cents for what it is worth.
