Well, for the most part I do trust them. I employ whats called a "click counter" it helps track how many times someone has clicked that link giving you a general idea of how many people are signing up under you. You can find several good and free ones @ hotscripts.com but, its impossible to track who actually signs up. I've been looking into some super advanced trackers that watch visitors after they leave your site that would do this wonderfully. But, trying to keep my visitors privacy in mind, and not my greed I probably won't impliment it.
But, your right it would be easy for them to screw us out of a couple sign-ups per month. If anything I feel bad for the indian affiliate manager guy whos making a couple bux an hour doing all the hard work though
--EG
http://www.Tips4Poker.com