Freedom of speech or common courtesy?

Politely turn around and say to the person in a loud voice. (Make sure you say this loud) EXCUSE ME. While I respect your freedom of speech there are Children present do you think that you can refrain from using foul language in front of them. This will not only get the inconsiderate SOB's attention it will also draw everyone Else's attention. Which will make the guy/girl look really bad and hopefully prevent them from going into a verbal rampage because they are embarred. I have done this a few times. The person usually ends of apologizing. I have even received applause from other customers.