In my experience, it hasn't been the merchants doing these add-ons; it's the credit card companies themselves. For instance, I call BigBank, the issuer of my Visa card, to make sure that my last payment was credited on time. I'm transferred to a customer rep who answers the question and then says, "By the way, I see that you're entitled to join our travel savings plan ... [blah, blah, blah about the great features of the plan]. You can have a free trial starting tomorrow." If you say anything except, "No, no, no," they automatically sign you up and then, after 10 or 25 days, X Travel Co. starts adding a "nominal fee" of $29.95 ("only pennies a day") to your card. If X Travel Co. is an "affiliate" of BigBank and you failed to opt out when BigBank sent you the notice of its privacy policies, then you don't really have much recourse except to call BigBank, talk someone into giving you the contact information for X Travel Co., and then contacting them to stop charging you.