In the past I've been able to buy physical gift cards on their website shipped to me to trigger the Lululemon offers I've had on Amex cards (i.e. spend $100 receive $20 back). The terms also stated that gift card purchases are not eligible but I've always gotten the credit when buying physical gift cards online and have done this quite a number of times over the years. So I'm assuming it will work for this credit as well unless they put in some sort of mechanism to detect that it's gift card purchase and block it from triggering the credit in which case it will stop working for Amex offers (and Chase too) as well.