I have bought Shell gift cards with a Sears gift card on 3 different occasions at my local Sears (most recent was two days ago). On each occasion I also bought some merchandise along with the gift card. I have no idea if buying merchandise with the gift card makes it different for the cashier, but since it's not particularly worth it for me to make a trip to Sears just for gift cards, waiting until I actually need merchandise from Sears works for me.