It appears Kazaa is stealing from smaller sites (mine included). Here is a description from the gnome of the low down dirty tricks kazaa plays:

Since Napster’s death, fans of P2P and file sharing have mostly migrated to software like Kazaa and morpheus. The newest version of Kazaa contains code which will rewrite URLs to sites like which allows affiliates to earn commission from sales they refer to Amazon. If you were to have this software installed and click through one of Lockergnome’s book links to Amazon, Kazaa would end up getting credit for any sales that may have resulted from your visit to the site.

Kazaa claims it’s all legitimate since they told users about it in the EULA, and it’s not really stealing from the end user. The problem is that it is stealing from the smaller sites that may depend on referral commissions to stay afloat.