Well, save files are not explicitly said to have their home in Application Support, because "regular apps" don't have save files, they have documents which the user can place freely. However, the *real* reason that they belong in the Library (for instance, I usually create new folders like ~/Library/Galder/Galder Saves.sav) is that you cannot guarantee write permissions anywhere outside the Home folder. (In particular, not inside or beside your app bundle, which could be run from a mounted disk image). So you need to put save files in the user's home folder, and in there, the Library is a pretty good place.