I believe one in five people go through life totally immune to the irritating oils from poison ivy. Another third have a seasonal or episodic sensitivity. That's the category I am in. Sometimes it doesn't bother me, sometimes it does. If one has any number of visitors to see their bonsai, I can't see how you would take the risk having poison ivy on their bench, given the litigious nature of our society.
But then again, I have a few orchids in my collection that have carrion fragrances, pretty to look at, but keep the nose away. So I do get it, fun idea. They are very pretty in autumn. But I wouldn't tell my home owner's insurance agency I had this in the yard.