Question: After which world event, did retail establishments in the U.S. began to pursue a high-volume, low-profit-margin strategy in a type of store that sells products at prices that are lower than the typical market value and for example sells Scotsmac, an alcoholic drink consisting of a blend of wine and whisky flavouring, in 700ml bottles?
Sentence (from "Discount store"): A "full-line discount store" or "mass merchandiser" may offer a wide assortment of goods with a focus on price rather than service, display, or wide choice - such as Aldi and Lidl; a "speciality", "single line", or "category killer" discount store may specialize in specific merchandise such as jewelry, electronic equipment, or electrical appliances, relying on bulk purchase and efficient distribution to keep down cost - such as Toys "R" Us and Staples.
Relevant evidence: No