[SpamCop-List] What am I missing?

[lt]

We spend a huge amount of time with Spamcop reporting to achieve very 
little. For every Spamvertized site there are probably 10,000 different 
sources for the spam promoting them. One report I just read said there 
was currently 4,000,000 open proxies for the spammers to use. By simply 
blocking access to the spamvertized sites the problem would go away in a 
very short period. AOL has already started, why are they alone in this 
effort. Anyone wanting to do business with a site that forged their 
e-mail address is obviously an idiot, so blocking these sites would only 
help the customers of the ISP's. And, I would think that it should be 
fairly easy to allow customers who really want to go their to be 
exempted from this black listing. Comments?