I think the photos are meant to imply that the system is reading external input as text and so might be vulnerable to an injection attack like what the bottom picture shows. I don't think it was intended to suggest that the system has actually been hacked in that photo.
Of course, the whole thing is meant as a silly joke (and that's one of the reasons I wish it wasn't posted here). It's unlikely that the camera would recognize something that's so obviously different from a license plate, let alone use a SQL database.
I'd love to see a real discussion on how the ubiquity of computers creates interesting vectors for attacking infrastructure. It seems inevitable that these systems will be connected to higher-value targets and that non-traditional input devices can still be used for launching attacks.
I think its interesting that in the beginning I assumed this was an american car/place because the SQL statement is in Eglish but in computer language, the reserved statements are English, even though this car in the picture is from Poland.
Thats what I dont get. On the car it looks like the driver is writing some other sort of License, ZU O666 but the sign is telling DW 530GS to slow down. Not enough images of the car to prove if it did, or did not tell the driver exactly to slow down. But for the sake of making this awesome, lets say it did work.
The second frame is telling a particular (valid) polish license plate number to slow down.