The rich have always been different from you and me, but this revealing and funny journey through “Richistan” entertainingly shows that they are more different than ever. Richistanis have 400-foot-yachts, 30,000-square-foot homes, house staffs of more than 100, and their own “arborists.” They’re also different from Old Money, and have torn down blue-blood institutions to build their own shining empire. Richistan is like the best travel writing, full of colorful and interesting stories providing insights into exotic locales. Robert Frank has been loitering on the docks of yacht marinas, pestering his way into charity balls, and schmoozing with real estate agents selling mega-houses to capture the story of the twenty-first century’s nouveau riche: House-training the rich. People with new wealth have to be taught how to act like, well, proper rich people. Just in the nick of time, there’s been a boom in the number of newly trained...