PLEASE tell me you are just kidding. PLEASE. I mean, you really need somebody to tell you that you are obligated to pay for additional product or return it? Jeez, why are there so many people like this? Do we blame their mommys for not teaching them basic rules about life?
Yes, you either pay for the product or return it. You don't get to keep it for free. And if you didn't get charged yet, just wait. They'll figure it out and you'll come back crying on here that you shouldn't have to pay for merchandise you didn't order. Boo hoo. Grow up.