I'll bite, how is a restaurant supposed to figure out which groups of people are "child groomers" as opposed to something more pedestrian and normal like "parents?"
So, we're gonna rely on the psychic powers of witch hunting cretins who work in food service; what could possibly go wrong?
I don't know what planet you live on where we need to deputize the country's wait staff to catch child molestors who meet their victims on match dot com and bring them to restaurants, but I don't want to live on that planet.
You're never able to read a person?
You don't think people working in a restaurant can't put 2 & 2 together and come up with 4 more times than not?
So, you see a person come in with different children repeatedly and act above & beyond affectionate to them. Inappropriate caressing/touching?
You don't think that's gonna set off alarm bells in the staffs' heads?