From a cursory look at Freddy Pharkas in ResEdit, it seems these are basically the same as in the DOS games, but as Macintosh resource forks. That is, you'll find they contain, for example, "MSG ", "SCR ", and "P56 " resources, with the same numbers they'd have in the DOS version, and some form of compression on each that may be the same as in DOS. Some other things like cursors, inventory items (because at least Freddy has a Mac-specific icon bar), and the sounds you mentioned are stored in a Mac-native format.