I think people create danger if there isn't any.
It's possible that people define an "other" and "different" because of natural human instinct.
"I wonder how many people who worry about radiation from tablet computers would think twice about taking their children for a holiday in Cornwall"
So what is this instinct and energy at play, for mothers to want to limit and control children?
Is there the ghost of "If you give a child everything he wants, then..." in there? ARE they trying to impress other moms, by saying "My child doesn't...." or "We don't allow..." or something? Joyce is right about what's adaptive—there ARE dangers. Fear can be the danger, though.
Maybe in the same way that if there's nothing in your stomach, digestive juices can start to hurt you a bit, if there's no real danger, the instinct to protect a child can start to feed on things that aren't really dangers?