A less virtuous person would just pay criminals a hundred bucks or some other trivial fee to have direct access to the data that's being collected (and mishandled) about him. The song and dance required to keep these leaks out of public sight only enables victimizers, and there would be a magnet link in this very thread if they didn't have deep pockets and a vested interest in relegating this news to a one-and-half-page internet news blurb.
Hashing an IP address (or phone number) doesn't add much security because such hashes are easy to reverse. Better idea is to delete IP address after some short time. You might keep it for a week on month to prevent mass registration, but after that time you don't need it.