I have read that many/most VISA/Mastercard merchant agreements prohibit merchants from requesting and/or recording additional ID from customers as a condition of sale, but I have frequently been asked to fax copies of my passport or other identification as well as a copy of the credit card itself to online vendors.
I am concerned about anonymous vendors having this sort of information in their possession - credit card information PLUS identification. Even if they have no malicious intent themselves, how can I be sure that they are safely deleting (or storing) my personal information?