we're screwed out of $50, right? i can't imagine if we go back to costco and show them our receipt, they will just hand over the tickets? how do we prove we never got them?
ETA: Thanks for your advice, everyone. I called the store and apparently the cashier or we were supposed to initial the receipt when we received the tickets. so all we have to do is go back and show them our "un-initialed" receipt and we'll get our tickets! whew.