It seems like all you have to do is buy a game for $2.99, but if you're not careful about the fine print, you might not realize that you may have ALSO been signed up for a monthly Game Club membership payment of about $7.
If you did this offer, check your account settings on the Big Fish site to be safe! You can cancel the membership (I just did, and I don't care if that stops my gaia cash confused fine, whatever) and delete your payment info, but it's pretty underhanded about putting it in place—the "why I'm canceling my membership" options even includes "I didn't realize buying a game would sign me up for a membership", and it's a major topic on their FAQ, so this probably happens often.
Should have known the amount of Gaia Cash for the offer was too good to be true. And that the site looked kinda sketchy. rolleyes
Anyone else run into this or other sneaky stuff on sponsored offers?