You know..? I kind of gave up on that question sometime back.
Then I found cardflip.com where I could at least get Walmart cards (used also for gas) for a total of 5.3% discount. That's 3.3 from the card, plus 2% using bitcoin -- code "bitcoin777" -- for checkout. They'll mail you the standard plastic card, or send you an e-card of the offering -- that you can have the Walmart Customer Service desk load onto your own Walmart gift card.
Sometimes I've them have BP and Shell cards there, too.
i will check it out