Unethical, immoral, obviously. Criminal? Not at all. Starting with different laws in different jurisdictions, over the difference of criminal acts and civil offenses to the point where an AirBnB is your private home and not a hotel ("obviously" you're allowed to film your own home right?).

If it's criminal or not is not a matter of simple opinion, but of the laws in that jurisdiction. DanBC doesn't deserve the downvotes.