This is true, but that only means there would be several different entries for each disk. If a TOSEC dat file included each of .ISO, .BIN, and .NRG for every CD32 title that exists, it would still be a reasonable sized dat. And there are some TOSEC dats that are just for DMS files or EXE files, so I could even see three different CD32 dat files if that was neccesary.
The existance of a CD32 TOSEC dat would probably propogate these files better, as well.
As for the mp3/wav thing....erm, I dunno.
Aren't the music tracks included on a CD image, though?