When people can be put on the 'sex offenders' list for having consentual sex with their spouses in their own living rooms, the title has lost all meaning.
Keep it for the predators, the actual molesters, the serial rapists. Not the twit who got drunk with some hook-up and didn't understand that "wow, I wanna fuck you so har--hurrrrrl" was a signal that he needed to walk away now instead of waiting around till she felt better. Not the guy who was just as drunk as his date, and thought that maybe her ripping his clothes off him, sucking his tonsils out, and saying "fuck me hard" was, in actuality, a "no, I'm too drunk to have sex with you." because we all know that women are just not responsible enough to know what they are doing when they are drunk. unless they're driving a car. or doing anything except having sex with a big, strong, responsible male. (if you did not note the sarcasm there, please get your detector repaired.)
So some asshole shows off his wee wittle winky to some girl. Now, how is she hurt by this? If it's on the street, and he's just some random assclown with a problem, it's a matter for the public health police, and a well adjusted parent tells their kid "wow, what an idiot." and doesn't make too big a deal out of it.
Now, if the exhibitionist is a teacher? and the exhibition takes place in a secluded or private area where the adult has brought the kid, and it's surrounded in secrecy? Yeah, then the kid is harmed. Not by simply seeing some penis, but because of the secrecy, because the kid is made to feel ashamed, or afraid.
A teacher who cannot control his/her exhibitionism while in the classroom, or around students does not need to be in charge of kids. The same with a teacher that cannot control her/his language, and continually says things like "Fuck you" "You Cunt" "Bush is a great Prez" in front of kids. People, control your impulses, please.
Kids, normal kids, see their parents naked. Sometimes it's because Mommy is taking a shower, or Daddy has to use the only john in the house while kid is taking a bath, or because Mommy and Daddy are comfortable in their own skin, and want to teach their children that there's nothing obscene about the human body.
Keeping everything shrouded in secrecy hurts. It causes festering, it causes fear, and if a kid is taught that there's nothing wrong with seeing someone else's nudity, but EVERYTHING wrong with being told "don't tell anyone what we're doing" or with being touched against their will, the kid should be able to tell their parents without any fear that Mommy and Daddy might be angry with them.