Yesterday I had to get several bottles of prescription medicine, some for each of us, from our local grocery store pharmacy. I always staple the cash register receipt to the empty bag with the labels, and then keep them in case of any question at the end of the year, and this was especially important as one bottle was for some rather pricey antibiotic. (Aside: I am very thankful for a good doctor and modern medicine when needed!)
Later, while working in the kitchen, I discovered - the receipt for the medicines. What had I stapled to the empty bag with the medicine labels? Sure enough, I had carefully saved the receipt for hamburger buns and Cover Girl makeup, and had almost thrown away the one for the medicines. Sigh.