I have the Saks Fifth Mastercard and use it rarely. I've only accumulated enough points to receive a giftcard on two occasions over the past few years (rather than cash back or other rewards, Saks rewards can only be used toward purchases from them). Both giftcards have proved to be incredibly frustrating to use online. Once a small item is purchased with the points, I've in both cases had to pay the remaining small amount (under $2.75 both times).
However, that's where things get tricky. Rather than just putting that small amount onto the Saks Fifth card, they put it onto a hypothetical "SaksFirst" card. This is not a card that I've ever physically had, and then when I try to pay it I've experienced the worst customer service of my life. Inept chat personnel who don't understand that I want to pay the balance online, but have no way to access the "SaksFirst" account since I have no idea what my account number is (I only have the Mastercard!), etc.
The last straw is a statement that I just received charging me 0.2 - that's correct, 2 cents, of interest on the $2.67 I paid last month. I've never paid interest on a single credit card in my entire life up to this point, and although it's a very small amount, this is absolutely the last straw. I would be remiss if I did not very strongly warn all others against any involvement in this ridiculous store scheme for confusion and grief!