Free TiVo basic vs. full TiVo features

Free TiVo basic is no longer available on any TiVo machines and has not been for a couple years, as I understand it. Only on certain Series 2 units like the Toshiba with DVD recorder.

Sooo... as a software engineer I have to ask - at this point why go through all the hassle of maintaining a set of code to restrict the TiVo features and the 3 day program guide, even though internally the unit has 14 days of guide data? And to restrict the user interface in terms of showing the now playing list differently, etc.? Seems kind of like a waste of time to me, since that is such a small minority of the TiVo owners. I can understand restricting features that require resources directly from TiVo, like being able to remotely program the unit over the internet, etc., but there is most likely a large amount of code that could go away if you decided to just get rid of it, thus you would have less to maintain and WAY less to test each time you do a build.

I cannot see the sense of it from a software engineering standpoint, at least from a cost of support standpoint. Why do it any more, since there would be no loss of revenue stream at this point, but there would be a gain of source maintainability?