It wouldn't have cost them much to draft Griffin, negligible amount, but you pass on picks and invest a lot more money in the QB position even though most of it is a sunk cost at this point. Whatever, as long as they nail a few of the extra picks and pick up a replacement QB down the road they'll be in a better position to compete but if Griffin does what's expected of him, the fans will never forget. It'll take a QB of equal talent to get them to forget.
Still, they got a shitload by moving back three picks or so. Two first round talents with their top two choices, and they have 4 first round selections in the next two drafts. Ammo to add talent or to move and choose a QB if they feel the need to. Much more flexibility, but they had to pass up on what might be a generational talent, or not, too soon to write the book.