Safari :: Software To Block Cookies?

stop selected cookies from being set in Safari? For instance, I would like to permanently block cookies from, say, Facebook and Google Analytics. I have tried clicking the radio button in Preferences>Privacy that supposedly blocks cookies from Third Parties and Advertisers, and like many other users I have found that it does nothing. I get just as many cookies from third parties and advertisers whether the button is clicked or not. As far as I can tell it’s a placebo. 

Apple’s Safari help on this issue is suspiciously carefully worded. It says that if you click the radio button, “this MIGHT HELP prevent certain advertisers from storing cookies on your computer.” What?!! What’s with the “might” and “help”? Talk about weasel words! Does it work or doesn’t it? Is it so difficult for software to recognize and delete a cookie? I find it pretty hard to believe that the problem is technical and not, um, deliberate. Apple is, after all, in the information business just like all the other major players. 

Anyway, the software that people usually recommend for zapping cookies is Safari Cookies, but that deletes them only when you quit Safari – in other words, after said cookies have reported back to their source. So what’s the point? By then they have done exactly what you are trying to stop them from doing. I want the cookies deleted when they are set – BEFORE my privacy is compromised.