More like the french don't give a fuck about what you do in your private life, and it's actually refreshing to see a president that is happily married and doesn't embarrass himself by spending public money to try to hide his double life.>>110157614
That's not true for most of those countries. If you've reached the age of sexual consent but not the age of majority, at most it'll be used as an aggravating circumstance in case of sexual assault.
Same with incest. Not an offense if both are consenting, but an aggravated circumstance in case of rape (except in Danemark and Germany, where you'll get both fined even if there's consent).