This episode "predicted" two events set during 2014 FIFA World Cup Brazil (2014) in Brazil: Neymar's concussion which was incredibly similar to El Divo's accident, and Germany's triumph over Brazil (with 7 goals over only one).
An earlier episode, 'Blame it on Lisa,' was also set in Brazil and apparently angered that nation's board of tourism. One major complaint was that the episode implied that Brazil was overrun with monkeys. In response to these complaints, The Simpsons made several more jokes at Brazil's expense (Krusty saying that Mr. Teenie's uncle was head monkey for the board of tourism; Homer saying "I'd like to go back, but I hear the monkey problem has gotten worse."). Even this episode depicts a monkey on the tail of the plane that takes the family to Brazil.
The actual 2014 World cup final was Argentina vs. Germany.
Despite both Martin and Lisa putting emphasis on the Marie Curie's French citizenship, she was born and raised in Poland and was strongly proud of and connected to her Polish heritage and upbringing.
Ezra, the Stuffwich Sandwich spokesman, is a parody of Jared Fogle, who became famous for appearing in ads for Subway sandwiches until his 2015 arrest and is currently serving a 13-15 year prison sentence.