You have to delete cookies and browser history to stop the ads following you around. Unfortunately the average web user only does this when they buy a new computer or other device that connects to the internet.
IBA ads must make more money for Google or they would show them, and as everyone knows Google is all about making money.
Adsense publishers are like pesky little flies than steal a tiny little bit food off Google's plate and they have a big fly swatter to deal with us. Sooner or later you're going to get swatted.