That's really that problem with every recommendation system that actually offers you something of worth, isn't it? When I wrote the referral system, I wasn't aware of the fact that people might read something into it. I was basically coding away and thinking: "Well now that I used the referral code, I might as well remove it. Nobody needs it anymore."

As people started complaining that their links didn't work - which in fact, they did all along - we decided to leave it in the URL from now on. Such is life ;)