My main reason for using FLAC is for archival purposes. Even though MP3 is basically universally supported, if I needed a different format for some reason, I would want to start with a lossless copy rather than (for instance) making a lossy copy based off an already lossy copy. I have enough storage and it is cheap enough that I'm not really worried about file size. I generally convert to MP3 v0 for my portable devices though and leave the large files at home.
5/20/15 at 4:32pm