One technique used to produce the grafted JWP is to wire the JBP lower trunk with wire, plant it in the ground for a decade. The wire is allowed to cut in, and eventually covered over. This adds to the "rough bark" of the lower trunk. Sometimes it looks ok, sometimes not. As I said, they do these by the thousands. And cull out the really ugly ones, and hope to get a few really nice ones.
When buying one of these, try to pick one where the buried wire doesn't look like buried wire! Also, try to pick one where the graft transition isn't too much of a negative.
Also, be aware that the best examples of these trees get snapped up by the Japanese. The ones that are made available to American importers are those they couldn't sell in Japan! These are the equivalent of the WalMart mallsai in Japan.
Here's mine:
