Name the law. No more evasions or non-answers; just tell us which specific law is being violated.
Name the law that says I can't.
Name the law that would be broken. Quote the statute.
Prove it.
I don't need to "go ask the authorities", because I already work in law enforcement. (I asked the question as a private citizen, though; my department has no jurisdiction over newsgroup posts by a Canadian).
No cop in any western country will consider your "because the person doing this ain't looking for this information to send Flymx a Christmas card. He is clearly going to do something else with this information" argument to be probable cause for an arrest or even an investigation. PROVE that I don't wish to send Flymx a Christmas card. Or that I don't wish to simply announce that [insert name here] is the asshole who keeps crossposting into the coffee newsgroup where he is not welcome.
Name the law. Any answer that fails to cite specific language in a specific law will be considered to me further evasion and an admission of defeat on your part.