I believe it to be an ageist rule. Old people & Kids are to be seen & not heard. I happen to love smiling at kids in restaurants. And you know? If they're howling- their airway is open & clear (once a nurse, always a nurse). I use this same mindset when I'm on a plane with an upset baby & a frantic mother. It's amazing how making eye contact & smiling at the mother helps the situation. Suddenly, she's not alone with a crying child. Because all of us who ever had kids have been there - done that.

Kids are people too. They deserve to learn how to eat at a restaurant & widen their palate.