The Irony of Spam
The likely truth is that products sold via spam don't actually make any money. The people, who do make money, are the intermediaries--the spammers, who market themselves to potential advertisers via newspaper and other ads. I have spotted a few such ads such by spammers that attempt to lure businesses with the promise of reaching millions of Internet users and then capture a pretty sum in the process. The businesses that do respond probably don't see any sales from their first mailing and never return; but there's no shortage of inexperienced businesses that will fork over cash and fund the continuation of spam. On the other hand, maybe there are fools who fall for fake university degrees, cheap printer cartridges and penile enlargement pills.
I am hopeful that the spam problem will go away in a few years, for the simple reason that bright minds at Microsoft, AOL and Yahoo are working on it, and that unusable email, if spam does accelerate at the current rate, will force the abandonment of existing standards and spark new, more resilient technology.