I have the same experience.
I have a web store, and one of my customers saw this $9 charge on her credit card statement. When she called to find out what it was, they told her she'd signed up for this rewards program via MY website. I, of course, was appalled, could not imagine how that could be true (thought maybe they had hacked into my servers??) and so I called the folks who provide our secure credit card processing (www.virtualcart.com) to see if they could shed any light. Turns out, they were 100% aware of the stupid thing in fact, they signed up for it.
Here's how it works - shopping cart providers (like VirtualCart) have an agreement with this company (Webloyalty, aka WLI Reservations Rewards) whereby when a customer gets to the confirmation page of a transaction in a store that uses a VirtualCart shopping cart, they see a little box saying: Your purchase is complete. Click here to claim your $10 Cash Back Reward on your next purchase!"
It looks, for all intents and purposes, as though it's part of the store that you're on but underneath the "Continue" button that you can click, in small print, it says "By clicking above, you can claim your reward from the reward provider, Reservation Rewards." It basically banks on the assumption that customers trust the site they're on, THINK they're getting $10 back from that store, and so they click on it. Once you click on it, it pulls your credit card information from the site you just used, and signs you up for this Rewards" program.
It's the most godawful scam I've ever heard of, but as I said, the people providing cart services to vendors have CHOSEN to be part of it (although, in my case, as I suspect in many, without the vendor even knowing!!). When I spoke to my shopping cart provider, they were quick to tell me that they thoroughly researched this program, that places like Yahoo and Expedia all use it, etc etc.
I then had to formally submit a request for them to DISABLE this stupid thing on my web store (I couldn't even do it myself through my control panel).
It's a pretty hideous scam, but that's how it works.
Rochester, New York