Starting in June, Costco members can get 15 dollars off up to 6 bags (6.4 pounds, 90 servings) of optimum nutrition protein. Current prices online show 60 dollars per bag, giving a likely price of 45 dollars after discount. Online flavors include vanilla and chocolate. Online shipping is estimated at $2.99. In store prices and selection may vary.
This comes out to about $7 per pound, slightly lower than the $7.50 with the current Vitamin Shoppe deal. And, you don't need to commit to 8 pounds of a single flavor to get this deal.