In this case, the question was rhetorical - the original release of BG1 takes 5 CDs, and the sixth is the Tales of the Sword Coast expansion. Installed the game takes around 2.8GB IIRC.
They did eventually re-release it as only a 3 CD set because they could cram more data on a single CD by then.
An uncompressed CD audio soundtrack, maybe?
(I’m not familiar with Baldur’s Gate in particular, but I do remember some '90s games being like that.)
You could do that with a lot of PS1 games. The first track was data, the rest were just regular CD audio tracks.
This got rarer later on, once they realised the could fill the discs with FMV sequences instead.
In this case, the question was rhetorical - the original release of BG1 takes 5 CDs, and the sixth is the Tales of the Sword Coast expansion. Installed the game takes around 2.8GB IIRC. They did eventually re-release it as only a 3 CD set because they could cram more data on a single CD by then.