I overtipped the Instacart driver who brought me my prescriptions from Costco, but oh well. He'll probably be very grateful. I now know why I've never taken advantage of the "you could be eligible for free delivery" from Costco's pharmacy before: it isn't free. It cost $8. Plus the amount I tipped, which I did try to change, except I made it higher instead of lower. (This danged newfangled thing called the Internet--someday I'll learn how to use it real well!)