If you're so rich, how come you're not smart?

I did a radio interview today. The host asked me what was the common theme in my books. I said, "If you're so rich, how come you're not smart.
what ZI was getting at was: why do people with money make their investment decisions with their emotions, so they fall for schemes, fads, bubbles? It's been going on forever, and shows no signs of slowing down