That depends on what you mean by "giant." The confectionary on Main Street in the Magic Kingdom is the only place I could find the giant (they were 8-10" in diameter at least and cost over $10 a piece) Mickey rice crispy treats. And trust me, I looked. I looked along the Boardwalk, in BC/YC, at MK, Epcot, HS, AK, and DTD; in WL, SSR, GF, Contemporary, Poly, and in AKL. Most of those places had the traditional sized Mickey treats in chocolate and/or plain that cost under $4 and could be used as a snack credit.