The MSP suggests buying milk, then returning it for exchange stating that you meant to get 1%, or some such. Others have suggested buying a case of something - water, soft drinks, beer, etc. This meets the bottom of the cart requirement, as well. Return it to the store for refund, stating that your spouse/sister/bff, texted you that they had just purchased it. The return or exchange can be done as quickly after purchase as you think you can pull it off.