While even the biggest cynic in me believes that there's a lot of truth in this, there's also something to be said about overall customer satisfaction, leading to better sales.

Don't forget that for any device that a child owns, the likelihood is the parent is the customer, and it's their repeat purchases that probably make the biggest difference.

It may be a big opportunity for Apple. After all most of their income comes from device sales, not from app store. Offering tools for parents which make them feel good, might cause them to spend the extra $100-200 per kid and get them iPhone instead of cheaper Android device.

Of course others could follow with similar features and this would remove the possible advantage Apple had, leaving them with no advantage and reduced app store revenue. Or if others don't follow, this might drive developers to other platforms.