I will say based on dealing with other auction houses I was used to getting an invoice and calling in/making a payment. I was a bit surprised when I got the email that my card had been charged. then I went back and read the terms closer and realized I should have expected that - my fault for being surprised, no one else's. The only difference this makes to me is to make sure going forward that I register with the card I intend to pay with.
Sorry you had a bad actor.