I agree also! I have an almost 10 year old with ADHD/ODD and if I can do it anyone can! Although he hasn't had a tantrum in many a year, it was not a pretty sight to see me physically lugging a a big 6 year old out of stores and restaurants until he calms down. But it works! Consistency is the key. If you react the same way every time, they learn pretty quickly what the consequences of their actions will be.
One of the biggest problems I've seen is parents that don't really know how to utilize 1-2-3 magic correctly. They do "1...if you don't stop this then that will happen, then they wait a couple of minutes, 2...I'm warning you, stop or else, then they wait another couple of minutes, then, I'm almost to 3, do you want to get punished? I've given you 2 chances, etc, etc, etc." then finally the say 3 and deliver the punishment. In reality you tell them to stop. If they don't, you say "1...pause... 2...pause... 3" then deliver the punishment with no more words spoken. And everytime they start up again after punishment has started, then the punishment starts all over again right back at the beginning. It took awhile for us to learn how to do this correctly but boy did it work!!! I even started carrying a small digital timer with me. As he got older, the sight of me taking the timer out of my purse was often enough to stop my son in his tantrum tracks!
Also, please don't judge a child in the middle of a tantrum as a "brat"!!! Some children have disorders that make it hard for them to control their emotions. So, next time you see a child in the middle of a tantrum, please remember that they may be embarrassed by their own behaviour but unable to control it. My son used to cry after a public tantrum because people were looking at him and he was ashamed of how he acted. After one particularly bad episode during which a complete stranger came up and said "if that was my son, he'd get a good whack on his a**", Jace hugged me after it was over and cried because he thought that the woman thought that I was a bad parent and it really upset him.
Sorry for the rant, this is just a pet peeve of mine