The flying red convertible also suggests that Sandy is happily being whisked away to heaven at the end of the movie.
They actually represent various political figures from the Enlightenment and the Big Bad Wolf is the oppression of respectable society.
Turns out, it was all just in the mind of the Reddit user who first came up with the theory though.
The line, “I saved her life, she nearly drowned,” suggests that Sandy actually did drown and the whole movie is an elaborate musical fantasy due to the lack of oxygen getting to her brain.