Well, I very much doubt that a small child would be able to defeat the lock and I don't thing that even a master locksmith could get an ILS revolver to shoot any faster than one with no lock at all. By that same line of thinking, we should remove the locks from all our cars and houses because some criminals might be able to defeat them.
A small child is not likely to defeat a cable lock running through the barrel either.
When it comes to car locks, would you like to have to deal with an internal lock of some sort every time you drove your car, or a stand-alone anti-theft device like "The Club"?
Sometimes you get what you pay for, sometimes you only pay more for what you get.
Three shots are not a "group"...they are a "few".
If the Bible is the literal, infallible, unerring word of God...where are all those witches I am supposed to kill? (Exodus 22:18)