That is indeed commonly done in games. Egosoft's X series had (has?) just one massive 8+ hour, 128kbps MP3 file with all voice clips in the game, and just seeks to the needed position.
The games also used DirectAudio or some other horrible mess that relied on registering codecs to the OS, so one of the most common tech support complaints was that the game didn't play any voices (regular SFX were uncompressed WAV), because the user only used media players that bypassed Windows' central codec registry.
Re-encoding everything to WMA (guaranteed to be a registered codec) was suggested several times to management, but since they all used Windows Media Player with properly registered codecs, they never really got the severity of the problem, and didn't care that the fix would cost them nothing (the community had already done all the re-encoding work). I imagine it got changed later, when the games were ported to other OSes, but I had left by that point. (And my NDA expired a long time ago, too.)
So, yes, something like QOA that you can just drop into any C(++) codebase, as games tend to be, without licensing problems or run-time overhead, would have been really, really useful 20 years ago. The file size differences might have been a headache in the CD games era, but by the time DVDs became standard it wouldn't have been a problem.