Have a look at the following 5 ads, spanning the 1930s and 1940s.
Each on their own is fairly innocuous. Together they seem to suggest that the subject of a man in a bathing suit and a man in a robe or suit together might constitute something more communicative than simply a random happenstance. It appears to be a real theme27tell28
Young bathing men and older men in robes or suits watching them:
Penn Maryland 1935 ad - the year after Repeal.
Hiram Walker gin, late 1930s. Older man in robe watches bathing men pool-side.
Kinsey Blended Whiskey ad - mid 1940s - detail. Poolside highballs.
Old Sunny Brook blended whiskey ad - 1947. Older man in a robe greets a younger man in a bathing costume.
Old Sunny Brook blended whiskey ad, 1949. Bathing man in pool signals to a rather eager man in a suit.