because dressing up as Hitler and having cocaine and hooker parties in Vegas show a good moral foundation....
They are, and especially were, young. Never heard much about hookers though, the dress-up showed independent spirit and readiness to break a taboo. A king is not supposed to be a saint, nor is a saint supposed to be a prude from birth. Qualities for a king are courage (both served in active units) and independent thought (see above).