Selling photos of public figures you have taken yourself is in no way a copyright violation. It's how news and sports photographers make their living. The copyright belongs to the photographer. Taking pictures at an event where cameras are supposed to be banned raises ethical questions but is not illegal.

Taking concert pictures and then selling them certainly violates "fan" ethics. Same goes for those that ask for an autograph and then sell it. I wouldn't do either and I'm sure most, if not all, fans here feel the same way.