StackSocial review: Costco membership process... Very convoluted and they are non responsive after first issue.

I got a Costco offer on my email, which was unsolicited. I presume a web search initiated it. Offer and website seemed like a groupon knock-off and since Groupon didn't currently have a Costco offer I signed up for it, thinking that it would be pretty easy. Well it was not. Had to fill out a stacksocial membership, and was a guest and was told I got an email after I checked out, but they would tell me what to do next. The email was in my spam account, and why I asked them what to do. I empty my spam account frequently, and then followed their instructions on how to sign up and use the redemption code. The sign up is a lengthy process on the Costco site. I did this on my Ipad, and the redemption code starts off with 4 letters and ends with 3 numbers on my Ipad, but when I pulled up the email on my windows computer the O in the middle of the what looked like 904 was really 9O4. That caused the promo code not to work in the Costco site, and I got errors and corrected everything that was in Red on the form, which included credit card information. So what happened is I paid Stack Social, and Costco. I got a lecture from StackSocial that said "we didn't tell you to input your credit card", and then they quit returning my emails. I was angry enough to not get a Costco card but Costco was good enough to work with me and try to settle it with them.