I think people are looking way too much into his character for these things. I have always been of the opinion that fame and money don't necessarily corrupt a person and suddenly make them hedonistic and degenerate. It is generally the case that excessive amounts of money and fame exacerbate minor character flaws. For example, someone who has a minor drinking problem would likely become a full-blown alcoholic. Or maybe someone who enjoys a bit of gambling every once and a while is likely to become a chronic gambler and lose millions.
Most people are kept in check by their financial inability to take their vices to the extremes, money doesn't create the vices, it only gives people the ability to take them to insanely high levels.
In Nick's case it's likely he had a habit of taking risque photos with his wife, which surprisingly is something a lot of couples do, especially affluent ones. I remember a buddy of mine talking about how his extremely liberal parents (both of whom were Doctors) took photos of themselves semi-naked next to an old General Lee car, confederate flag and all.
You take that relatively minor perversion and add in a discord with however many thousands of people, yeah it's gonna be a lot worse. It's surprising that a guy as smart as Nick can't notice that behavior in himself, but I suppose character flaws are most obscured to the person suffering them.