Other mistake: After Bruno and Lutz had been arrested and are outside the police station arguing, in the background in the left corner, there is a gold Ford Mustang. Then as Lutz is walking away, the same gold Ford Mustang is seen driving in to park in that same place.
Other mistake: Throughout the movie, the subtitles for Bruno and Lutz translate everything from German to English. When Lutz carries Bruno on his back from the restaurant, he says "Herr Bruno", and the subtitle should say "Mr.Bruno" but says "Herr Bruno" still.
Chosen answer: The MPAA's rating guidelines are all over the place, and tone and context matter. The scene in question appears to be real, but there's not really anything explicit shown, and since it's all played for laughs, the MPAA was probably more lenient on it.
Phaneron ★