Good Wired article on the subject:
A security flaw at a website operated by the purveyors of penis-enlargement pills has provided the world with a depressing answer to the question: Who in their right mind would buy something from a spammer? An order log left exposed at one of Amazing Internet Products’ websites revealed that, over a four-week period, some 6,000 people responded to e-mail ads and placed orders for the company’s Pinacle herbal supplement. Most customers ordered two bottles of the pills at a price of $50 per bottle.
And check this out for bizarre:
An investigation … last month revealed that Bournival’s mentor and business partner is Davis Wolfgang Hawke, a chess expert and former neo-Nazi leader who turned to the spam business in 1999 after it became public that his father was Jewish.