Costco wouldn't put non-run flats on a run flat equipped car.Sam's stocks and sells mainly the same high end products as Costco, not the cheap chinesium that Wal-Mart stores have for pennies.
That said, I don't really see a reason to buy at Sam's over Costco since Costco's care policy is included and seems to be a better deal.
Dealer would but it cost more.
Sams did and it was same price as Costco.
Weird.