There is no way they are tracking who received the offer. First of all, the promo code is the same for everyone. Second of all, it does not even have my skymiles number on it (if they knew who I was, they'd know I was gold already, and ready to bolt). Third, it does not even assume the recipient is a skymiles member - saying to sign up first if one isn't. Fourth, they can't even be tracking it by zip code, as it was sent to me at my office, but if I was signing up, I would use my home address.