FLAC is for idiots who think they have superhuman hearing.
FLAC is also for users that want to store the original audio without any losses.
You can always encode and compress the audio again to suit your purposes, but you can't go backwards from a lossy format into a lossless one.
Whether this is for permanent future compatibility or because you wish to work with, edit, mix the audio in some way is another story.
But there's no reason to support what is essentially a worldwide standard for losslessly compressed audio, except of course because it doesn't support DRM..