Objectively, they're meta-data, on the order of box scores from a baseball game or the cast credits from a movie. So there's no particularly solid argument for them to infringe on the copyright of the original work.
- game: a baseball game is not a "work" under the Berne convention
- cast credits: they are descriptive, but not derived from the movie.
One of the criteria to assess "fair use" is "was anything creative added in the process of making the derivative", which is per definition not true in the checksum or fingerprint case. I don't find your argument compelling - it's not a closed and shut case.
They're not really meta-data - they describe aspects of the sound recording, just like a list of notes and durations would (ie a MIDI file derived from analysing the recording).
