Remember back in the late '60s and early '70s when gas stations would give away glassware and cutlery with every fill-up?
Goes back further than that. The practice started back around or shortly before the Great Depression. My family has a near complete four or six person setting of Green Horseshoe pattern glassware acquired through those fill up gifts back then. (one setting is plate, salad plate, cup and saucer, soup bowl, plus we have the serving trays punchbowl, ladle etc. The only thing we don't have is the covered butter dish.)