Just noticed the same thing today. I responded to a $25 off next Expedia reservation and thought it was through them. I can't believe I put in my credit card # on the offer page but if I did I guess I'm partly to blame for not reading everything. Nevertheless, I am positive it never clearly explained this "rewards" program had an automatic MONTHLY payment of $12 to get the $25 offer (and other coupons which are available all over the internet free of charge if you look)
I called and explained how I'm going to issue a complaint with the CT Attorney General's office (which I am) and they quickly issued a refund of the $48 (which have to see if it's true but seems to be). I will also be telling Expedia how I'm not doing future business with them since they give this company access to their customers. I fly at least once a month so hopefully that hurts them.
Obviously this company is fully aware of their shadey practices and I bet have been sued before. I say this since when you call their number, 1-800-732-7031, the first automated promt is for info on cancelling membership, press 1. Then it's for hitting #1 again for info on how to "immediately cancell membership." I choose to speak with someone and he immediately when into an explaination of what Res. Rewards is all about and how I become a member. He offered to cancell my memmbership right off the bat since 99.999% of their incoming calls must be for this reason! I told the guy that I know it's a tough job market, but please try to work for a more ethical company!