Hmm maybe I'm missing something....
The link above is for the Adorama deal -- for the same price, with a lesser lense + $45 gift card as an additional incentive. (So let's pretend apples to apples on the lenses -- and adorama is $50 less than Costco). Within the same Adorma deal above it says if you want the 55-250 lense, you could get it for $100 more from BHphoto -- making the B&H photo deal the same as the costco deal, except $100 more.
Seems to me that the Costco deal is better than both the Adorma & B&H deals if you are looking for the 18-55 and 55-250 lenses.
Spextar is referring to a deal like this one for $699.... where???