Apparently, nothing anyone says will change your mind, but here goes.

Basically any registration card you say at any hotel in the world will have a clause stating you are responsible for the bill. This would give the hotel the authorization (even without telling you, which was bad) to charge your card for any room costs, damages, incidentals, etc.

You got your money back in not a prolonged amount of time.

You can still write in, but I wouldn't expect much.