I saw the charge to my bank statement today for $7. Found this site which made it easy for me to go look up the web site (www.reservationrewards.com). I had to ask for my password since I had no recollection of ever signing up for this. Sure enough under my profile was my card number, name, address, etc. I decided to play it by their rules (as posted on the web site). I called the toll-free number and told them I wished to cancel and did not authorize it.
The agent was able to look up my record and tell me where my "membership" originated. In my case, it was from a reservation I made with Choice Hotels about a month ago and I was "given an opportunity to join the program" by clicking on a few buttons. I do remember the situation (kind of).
I do not think that I gave out my cc card number to them (I did use it to guarantee our room) but I do remember getting sucked over to that other site. I THOUGHT I was signing up for the hotel company's reward program and then realized that I had been a chump and exited quickly (but not quickly enough). I was told I should see a credit back to my account in 2 - 3 days. If I don't, I will simply refuse the charge via my bank's fraud policies.