[Editors’ note: The following post contains spoilers for “Game of Thrones.”]

“The Last of the Starks,” the fourth episode of the final season of “Game of Thrones,” featured numerous moments that got fans talking, from Cersei ordering the beheading of Missandei to Brienne losing her virginity to Jamie. And yet, no moment has gone as viral in the hours after the episode’s airing as the odd sight of a to-go plastic coffee cup placed on a table in front of Daenerys Targaryen. Was it a hugely obvious production gaffe or some kind of product placement? The answer is unclear, but press and “Thrones” fans delivered an onslaught of Starbucks/”Thrones” jokes on social media in reaction to the moment.

The coffee cup appeared early in the episode during the scene in which a majority of the main characters are drinking and feasting inside Winterfell following the defeat of the Night King and the white walker army. Tormund...