It's kind of funny looking back on albums like that, and the bonus content they would add. It was common early on to write the ToC in such a way that it skipped over a track, so Track 1 would be some ways into the disc, but there was data before "track 1" you could get to by rewinding past 0:00. Later, smarter CD players and especially computer CD-ROM drives wouldn't do that, so that practice started decreasing. But with computers, it was already commonplace for a video game to take up a small fraction of a CD, and then fill the rest with the soundtrack as red book audio, and CD players could still play the music. So they did that for awhile.

There was a brief moment in the mid-2000s where the record labels were feeling the threat of iTunes, so they tried adding value. I have a 2005 copy of Bon Jovi's Slippery When Wet which doesn't have the Compact Disc Digital Audio mark anywhere on it, because it's a DualDisc. It's a CD with half a DVD on its back; so it's slightly thicker than a standard CD and thus non-conforming to the red book standard, and . The CD side is an otherwise conforming red book audio copy of the album, but the DVD side features a very high quality stereo recording, a "made 20 years after the album was mastered so it's slightly janky" Dolby digital 5.1 surround sound version with added length, and the four music videos they recorded for the album in glorious "80's BetaCAM transferred to DVD" 480whatever.

Remember when companies tried to compete on benefits and features?