It’s all about perception.
The question being asked by this video is “how will people react if we drive supercars at normal speeds but play audio to make it sound like we’re racing?” They’re calling it a prank, but anyone who is paying attention to the actual speed of the cars can plainly see they aren’t racing. Yet people are falling for it, especially the police. We’d say it’s more psychological experiment than prank, although that would probably involve less giggling.
It’s still fascinating to see how many people simply refuse to believe what their eyes are telling them.