When my kids start to act up in public and I have exhausted other options, I remind them that Santa is always watching to see who will get presents at Christmas. Then I look for something that could be a hidden Santa cam and when I point it out, that is when my kids start to calm down.  At a restaurant it is usually a small speaker that is hanging on the wall; I tell my 5 yr old that it looks like a speaker but it's Santa's way of being secrative.  Whenever they actually see the hidden Santa cam, it makes a difference.