Right, I really don't get it. There must have been some incident ...
According to Rowe, he was told that he was starting right before the game, and he acknowledged that Butler practiced in those mythical "packages" that Belichick/Patricia referred to during the entire week.
Butler did fly in late because he supposedly had the flu, but I doubt that has someone to do with it.
I understand that Bill always values sending a message over winning one single game. However, when said game is your 40-year-old star QB's potentially last SB, perhaps it's time to apply a little "situational football" decision-making?
edit: Correction. Rowe reportedly said he practiced as CB2 the entire week, and apparently Butler was still under the weather as late as Thursday. Still, however, he was apparently well enough to get ST snaps, and I don't see how playing Bademosi/Chung over him in nickel packages is the better football decision. Certainly not after it has become clear that your defense is having issues closing down after the catch and tackling (coincidentally, both of these are Butler's strengths).
Butler played 97% of defensive snaps during the regular season. That pretty much means he was on the field at all times, regardless of matchups. I guess he was good enough back then?