> You would think that when you hand someone your telephone number and they promise to secure it or only use it for a specific purpose, the onus is on them to prove they didn't misuse it.
How could this be acceptably proven, in your opinion, if at all? "This information has never been misused" is the null hypothesis; it can never be proven for certain, from the moment the information is out of your direct control.
Proving it is another issue all together. Raising a reasonable concern that it was misused or mishandled triggers the process. And the process will uncover the the facts of the matter. For telephone numbers, the laws and regulations are pretty well written.