I basically came here to say what Shorty said. It doesn't ruin the Hannah Montana image at all. Her performance then and the show then has nothing to do with who she is now. Also, most of the time when people say that their childhoods are ruined, they're being facetious.

Also, celebrities doing bad things doesn't have anything to do with society. Maybe you follow these people as a religion, but most people really couldn't give more a smurf. Like, WHO CARES? It's not your life. If you're looking up to or trying to emulate a celebrity, then you're not that original of a person. And if they do bad things and you still look up to them, whose fault is that but yours? They're just people who happen to be well known for the media the produce. If Miley was a normal girl on the streets, I seriously doubt you'd even think twice, if only because you wouldn't know what she did in her private life.