It was rather common for PC games to include regular everyday “red book” audio for background music; I seem to remember back in the day you’d actually have to hook the optical drive to the sound card with a cable so it could pass through audio.

The Secret of Monkey Island did this for its CD releases; the audio options for that game ranged from PC speaker to Ad-Lib chip tunes to Roland MT-32 support and eventually CD Audio. The game shipped on a few diskettes, a few megabytes tops, so the whole game is tiny on a single 750MB CD, plenty of room for extremely high quality game audio.