It was crazy expensive.
Not only the delivery fee, the tip, etc. But every item was marked up significantly over the in-store price, with no indication that was the case. We even pulled out some old receipts to verify this price difference. Apparently part of the business model is to basically double charge both a delivery fee as well as hidden fees for products.
The total bill was a full 30% higher than going to the store. On a $200 bill for a Costco run, that's a $60 upcharge.
No thanks, I'd rather go myself in a hazmat suit and then powerwash all the groceries when I get home.