If ISPs charged customers $0.000001/email message, would it cure spam or would the spammers just continue to use third-party victims to spam and there would be lots of news stories about grandmothers and orphans getting huge ISP bills? IANAL, but many spammers are already breaking a law by using victim machines without authorization; but would law enforcement be more likely to do something if the victims now had a $50,000 bill from their ISP due to the unauthorized traffic?
There will always be crooks and victims. But if becoming a victim actually has real world consequences it is much more likely that people will try not to become a victim. I am not talking about sending bills for some outrageous amount due to excess bandwidth used. Instead cut off when a certain bandwidth threshold has been exceeded. If the bandwidth was used purposely and legitametly, buy more bandwidth, otherwise fix your PC. Adi