It is most certainly not a "I have nothing to hide" argument. It is a "what exactly is the value of a fingerprint in terms of identity theft?" It's a question of how dangerous, really, would access to the world's fingerprints be for a nefarious hacker. I'm not asking to be facetious, I honestly don't know the real answer relative to more standard security measures like passwords.

The same argument can be had for any individual piece of information. It's the amalgamation of all your personal data into the digital system of the internet that's dangerous, so it doesn't really tell us anything significant if your fingerprint by itself is valuable.