[knd775]

Uncompressed audio is apparently a huge portion of the storage footprint of modern games.

[ascagnel_]

Uncompressed, multi-language audio so publishers can ship one disc in all regions.

Microsoft supports per-region download slices, but I don't think many publishers take advantage of that because Sony and Nintendo don't support it.

[kristofferR]

Microsofts own Gears of War 4 is 133GB.