This last weekend I did the three pack of Costco ribs and for the first time was seriously disappointed. Each rack had a significant percentage of cartilage that I have not experienced in the Costco ribs before - it seemed like no two ribs were the same, and you could clearly see the joints between the cartilaginous tips and the bony parts of the rib. Many ribs had two cartilage bands at the end of the ribs. I do not know where along the rib cage these were cut because I'm definitely no expert, but it is the first time I have had such poor quality ribs from Costco.
I'll definitely be checking the packs closely the next time for "normal" looking ribs (even though they are good at hiding the bad parts).