Leosghost, that advertiser should not be targeting Karachi, should they? Google has spent a lot of time developing targeted ads and giving advertisers accurate geo targeting tools. If they don't know how to use them then that's their fault. If Google wanted you to filter countries in AdSense they would give you the tools to do so. I'm sure there are people that have valid reasons for blocking whole countries, but that does little against sophisticated attacks. Just don't go around telling people you're making more money because you blocked a bunch of countries, Google is very interested in that type of behavior.