If you are trying to use the AMEX 20% off offer to buy Amazon gift cards but are disappointed that it doesn't work here's another way to go. First buy up to $500 in Safeway/Vons gift cards and use your AMEX point(s). This should get you the $100 off. I would have plastic gift cards mailed to you as I have had problems getting cashiers to use egift cards at the supermarket stores. Next take the Safeway/Vons gift cards and buy Amazon gift cards. This works - I have just done it. However I would not buy over $100 at a time or the cashier may get nervous and refuse to put the order through. Then you would have to get the manager involved and turn this into a big hassle. Just do the purchases slowly and you will eventually get $500 in Amazon cards for $400.