Allen Adamson, co-founder of marketing services firm Metaforce and adjunct associate professor at the NYU Stern School of Business, pointed to consumer electronics store Crazy Eddie, which was at one point the largest chain in New York and had Christmas in July (and August) sales, as an example of a pioneer of summertime discounts long before Amazon.
https://www.adweek.com/digital/amazons-prime-day-proves-everything-old-is-new-again/