I think it sucks.
That said, I do think that parents who hire "homeless" people off the streets to do work on their homes for what ever reason, be it charitable or just plain cheapness, are playing with fire. The same could be said for parents who hold swing parties while their children are asleep in bed. That sort of behavior doesn't necessarily mean that the parents purposely contrived or arranged for their children to become the victims of evil, regardless of their naivete and/or thoughtless stupidity.
Reread the story that started this thread. Sometimes, children are stalked, preyed upon and taken by perverts. Many of those children do not survive. Elizabeth Smart and Leslie Gatto are the lucky ones. There is no doubt in my mind that the Smart family did not want this horrific thing to happen to their daughter.
There is nothing to EVEN suggest what you have presented.
No facts, nothing to back up your theory -- only your overly active imagination.
It is a sad commentary that you'd rather think the worse about the victim's family, even if you must make up stories.
I'm glad I'm not you.