The tale of Cinderella is often looked down on for being shallow and materialistic; Cinderella is only beautiful when she's in a dress, and the prince only likes her because she's beautiful.
But I think we have to remember how significant the class difference was between Cinderella and the Prince, and how truly big of a deal that union would have been hundreds of years ago. Even today there are some circles where it's really important if you come from money; but those class distinctions and judgments have grown much less significant. Especially here in America, where we tend to respect people more if they came from nothing and worked really hard to get where they are.
But the lines between royalty and servants were so untouchable we lose sight of the sacrifice the Prince made in being willing to marry Cinderella, a servant, even though she was found in her rags. It wasn't just her physical appearance, it was her station in life. The Prince instructed the shoe was to be tried on everyone, not just nobles and royals. It's interesting to compare Cinderella to the Villeneuve version of "Beauty and the Beast"-the whole thing is almost a parody of the class system, because she shows people judge others who aren't "good enough for them" (the Beast's/Prince's mother does not approve of Beauty, a commoner), then we find all the expectations of classes being turned upside down-in beauty verses ugliness, wealth verses poverty, royalty verses peasant, even fairy verses human.
In fact, I would argue that physical appearance is now one of the things we tend to judge other people by the most. It's almost our new version of ranking by class. I like to think that a modern version of Cinderella in the same spirit would be something like: a guy and a girl meet at a party, and he finds her very attractive and never forgets her. Years later he finds her, but now she has gained a lot of weight or in some other way become not as beautiful by cultural standards-yet he knows she is the same person from that party and because he fell in love with that girl he wants her no matter what. It can be read as a love that transcends cultural rules rather than falls into them, we've just morphed our rules a bit. Love at first sight in French Salon Fairy Tales is not the complete solution, but it was a step towards solving the problem of marriages that were arranged only for social status, regardless of the feelings of the people who would actually have to enter into that marriage and have their lives forever changed.
Illustrations by Walter Crane