As someone who has worked with convicted sex offenders for the past 10 years in my profession with the Department of Correction, Adult Felony Probation and Parole, I can tell you that your point is well-taken. It is very rare that I run across a sexual predator who "looks" like a sexual predator. That is akin to asking, "What does an alcoholic look like?" Believe me, the come in all shapes, sizes, genders, colors, religions, etc., etc. And, very, very few of them "look" like a sexual predator. Most of them look like Mom, Dad, Grandma, Grandpa, Uncle Bob, or Cousin Tom. That, my friend, is what makes them successful at being sexual predators. Would we let our children actually socialize with someone who "looks" like the man in these photos? However, we allow them to associate with all the above-mentioned people because they don't "look" dangerous. It's trite, but "looks can be deceiving." You wouldn't believe the number of people we supervise on Felony Probation or Parole whom you would never conceive of doing such a thing. They are respected members of their family, their organizations, their churches, their communities; yet, they have dirty little secrets. Unfortunately, we eventually discover that they aren't really secrets; others have known for a long time and have just kept things quiet or, worse yet, enabled that behavior. Just yesterday, we had a victim try to take her own life, at the age of 8, because her own mother accused her of breaking up the family because she reported to the police that her step-father was tying her up with a dog leash and hand-cuffing her to the bed while he raped her. The perpetrator is now doing 10 years in prison, but the victims of his crimes will serve life.
The more I know, the more I realize I don't know very much about sex offenders. I do know one thing: Like alcoholics and drug addicts, they cannot be cured. They have to learn their triggers, their limits, and their danger spots and avoid them. Many will relapse. Those are the ones for which we should be prepared because they only get better at it.