The thing is, in NBA 2k they have custom draft classes and the ability to edit ratings in franchise, which would allow a player to play with updated rosters and people still buy it year after year. If that became an issue, all they have to do is shutdown the servers after about a year and a half or two years, and people will buy a new one. And since roster editing already exists outside of CFM, reasons A and B are both probably not right. I think it more just has to do with EA not wanting people to be able to cheat in online CFM's. And also, reason B doesn't make sense, as after a few seasons, most stars' OVR goes down, and some of the franchise QB's end up retiring.