Haha, that's a really funny statement. Although I don't condone having sex with or exposing to sexual situations individuals below the limit stated by the law (in Western countries, anyway), it's still outrageous to say people who don't agree with the society's ethics have automatically a mental illness. Even the common ethics of today were revolutionary a little while ago, just like you said yourself. So, a person 100 years ago (in many Western countries) would have had a mental illness for thinking men and women are (politically, socially) equal? According to your logic a grand portion of the citizens of the USA have a mental illness because they either accept or reject capital punishment, opposing the laws of their particular state?
I'd say pedophilia is a mental illness condition, the rest are just preferences that should be suppressed by the individual (just like they mostly are).