Lord forgive me but I actually agree with some of Nova's post.
Children's behavior has gone down the sewer over my lifetime. I blame it on the liberal community that foisted "live and let live," free love, etc. When I was a child, I lived under "children should be seen and not heard" and every adult was a potential belt wielder. I feared the belt of strangers because I knew that my parents would beat me again if they found out. This meant that I watched my behavior when my parents were not around. Children that incessantly wail like banshees should be given something other than their selfish desires to wail about. If that toy or candy is worth wailing over and disturbing the peace of other patrons, they should be given something more reasonable over which to wail. A few stripes across the buttocks usually brings about a change of attitude leading to a change in behavior.
I am a realist though and see that that ship has largely sailed. Therefore, I submit that beating the adults or throwing the entire family out of the store might be a better strategy.