The "MENU" board above the grill differs from the folded menu that Olive ordered from. The board includes Spinach Stew and Spinach Goulash, while it is missing Spinach Steak and Spinach au Gratin from the menu.
The second poster Popeye shows his nephews is titled "Popeye A La Mode"; however, the actual title is Pop-Pie a la Mode (1945).
The safe in Spinach Heaven is of a size more appropriate for a large department store than for a small café with a menu that is unlikely to attract many customers.
Popeye's menu lists "TO-DAY'S SPECIAL" - the hyphenated form of the word had fallen out of use in the U.S. over a quarter of a century earlier.