There are spoilers for this musical here, but really? If you haven't seen the movie by now, what is wrong with you?
Oh, sure, it teaches us that society looks down on those with poor education and that with enough training and money any poor "guttersnipe" can fit into high society and it does all of this with wonderful music and a cast of actors (both on Broadway and in movies) that are always always lovely, Julie Andrews and Audrey Hepburn being among the women to play Eliza Doolittle. I admit that I'm slightly biased when it comes to my favorite, because no matter how lovely and talented a women Audrey Hepburn was, Julie Andrews will always hold a special place in my heart. (How could it be otherwise when I grew up on a steady diet of Andrews' movies, Sound of Music and Mary Poppins being the most watched).
But the real lesson taught here, despite the pretty songs and pretty actresses, is one that tells us that money and influence and security are more important than love and that, whether you love someone or not, you can become accustomed to them and even find them a bit nice to have around. As Professor Higgins says about Eliza:
But I'm so used to hear her say
"Good morning" ev'ry day.
Her joys, her woes,
Her highs, her lows,
Are second nature to me now;
Like breathing out and breathing in.
I'm very grateful she's a woman
And so easy to forget;
Rather like a habit
One can always break-
I've grown accustomed to the trace
Of something in the air;
Accustomed to her face.
And I suppose this could be taken as slightly romantic if it weren't for the fact that he quite clearly told Eliza, not but a scene earlier, that he did not love her and would never love her. In fact, despite that fact that Eliza returns to him at the end (instead of marrying Freddy, who is quite clearly in love with her) he never tells her that he loves her, nor does he apologize for the absolutely deplorable way he treated her for most of the story. This ends up making Eliza look like a push over for a man that will never really appreciate her. She comes back and instead of demanding an apology, just settles right back into the same situation she hated so much before.
And for what? Sure, perhaps she loves him. I Could Have Danced All Night (one of my favorite songs) seems to imply that quite strongly, but he does not love her. However he is wealthy and has a fairly secure life, which Freddy does not have. While I understand that this was an issue for many ladies of class at the time, I don't see why it would have mattered to Eliza so much. She was the kind of character that seemed much more inclined to marry for love and even if she had not chosen Freddy, well...let's just say that I've Grown Accustomed To Her Face is not the best love song. If a man (or woman) sang something like that to me, I would walk out on them, not matter how much I loved them, because they clearly didn't feel the same way about me.
That's really my only problem with this musical, though I'm sure there are several other plot holes I could drive a truck through. This is the only plot point that leaves me spitting made every time I watch the film starring Hepburn. Even though I know it won't change things, I find myself shouting "Don't do it, Eliza! Don't go back to him! Find someone better, anyone is better than that asshole!" Let's just say that Henry Higgins is not my favorite male and while some might claim that he becomes less of a misogynist by the end of the film...I just don't see it, sorry. He sees women as a bother and a nuisance still, except now they are one that he's gotten used to having around.