There are some programs with zero affiliates that buy traffic and have all marketing in-house.

I have to say that the affiliate business model needs some serious examination. There are some webmasters that can send a lot of joins, that know how to market, and are an asset to the sponsor programs. On the other hand, there are demanding drama queens that send 2 joins a month yet still want their money wired and want you to pick up the wire fees, or if they don't have a check in their mailbox on the day your Terms and Conditions say you send out checks [they forget it takes a day or two for delivery] they run screaming to the boards how you are scamming them.