I suppose, but $100 for a nenewal seems like plenty of money to run this system rationally. First, the whole interview thing is mostly theater. I guess my first interview was sort of an interview, I at least got asked a couple questions. No interview was done when I showed up -- after great effort -- at my renewal "interview" 5 years ago. Obviously, if resources are limited, you should not require optional interviews where your backround check is telling you that person doesn't REALLY need to be interviewed.

BTW, speaking of limited resouces, in my recent experiences passing through US Customs it's seemed like they have become significantly less thorough in screening people for stuff than they used to be. Going through Global Entry basically involved no screening at all. There may be good reasons for this -- they may know from their database what their real concerns are -- but if that's true, I don't understand why this interview scheduling nonsense is still going on.