Hope this helps! 

Shaw also manages to highlight the moral differences between the upper and lower classes in the English society through this scene. There is a clash of values and traditions between Colonel Pickering who represent the upper class and Alfred Doolittle who represent the lower class. Colonel Pickering has strains of the traditional Victorian prudery and is shocked by the revealations and frankness of Alfred Doolitle. Both he and Higgins are revolted to hear that Doolittle would be willing to sell his daughter for fifty pounds. One of the most prominent clash occurs when Pickering says to Higgins that Doolittle will make bad use of the money. He means that Doolittle would drink it away and spend it on reckless indulgence, instead of saving it. However for Doolittle saving money is a bad habit and so he immediately assures Pickering that he has no intention of saving the money but fully intends on spending it on a one night drinking spree:

Don't you be afraid that I'll save it and live idle on it. There wont be a penny of it left by Monday. It wont pauperize me, you bet. Just one good spree as for myself and the missus.

Later when Pickering asks Doolittle to marry his mistress, as he is against 'that sort of immorality' it is divulged that Doolittle is willing whereas the lady in question is not interested in marriage. She rather prefers to live as his mistress, someone he has to bring presents for and buy clothes for.This is unthinkable for any upper-class woman in the Victorian society. Thus, the conversation between Colonel Pickering, Professor Higgins and Alfred Doolittle highlights the main theme of the play which is the strictly enforced social class hiearchy based on language, and the various flaws in the system. 

Alfred Doolittle is a quintessential iconoclastic character who acts as Bernard Shaw's mouthpiece against the hypocrisy of the social hiearchy. The audience is first introduced to him during the Second act when he arrives at Wimpole Street to demand money for his daughter.  He came to know that his daughter is at Higgins's house and comes to claim his monetary right as a father. The bone of contention in the argument between him and Higgins is thus Eliza. The conversation between Professor Higgins, Colonel Pickering and the dustman Alfred Doolittle serves as comic relief in the play while at the same time pointing out the various idiosyncracies of the society. 

After he is announced by Mrs. Pickering, Alfred Doolittle barges into Higgins' study, asking for his daughter. He tries to intimidate Higgins and Pickering but is turn cowered by Higgins's threat to call the police against him and his daughter Eliza, for planning to extort money from him by tricks. He then confesses that he came there in hopes of getting some money. He calmly and confidently puts forth his arguments in such a reasonable manner that both Colonel Pickering and Professor Higgins is disarmed by his frankness and utter lack of morals. He puts forward what he considers to be a reasonable proposition in front of Higgins, that in exchange if his daughter Higgins should give him five pounds. When Colonel Pickering calls his claim to be not correct, he retorts back saying that he was an undeserving poor, and this was an excuse used by the higher classes to deprive him. He frankly and honestly points out the various faults of the hiearchy of the society. He is upset by the fact that he is deprived of most pleasures in life by the argument that he is undeserving. He says that his needs are as great as a widow who gets money out of six different charities for the death of one husband. 

But my needs is as great as the most deserving widow's that ever got money out of six different charities in one week for the death of the same husband. I dont need less than a deserving man: I need more. I dont eat less hearty than him; and I dirnk a lot more. 

He rants out against middle-class morality that deprieves him of the joys of life. He admits that he is 'undeserving' but that does not mean his needs in life are any less than a deserving man. Higgins is persuaded by his arguments and pays him five pounds, and Doolittle makes no pretence of saying that he would make a good use of it. He straightforwardly accepts that he will drink away the whole money on a spree in one night. 

Bernard Shaw through the character of Alfred Doolittle attacks the cherished and established institution of class hiearchy, which is also the theme of the play. When Pickering shocked by Doolittle's revealations asks him if he has any morals, Doolittle frankle says:

Can't afford them, Governor. Neither could you if you was as poor as me.

Here the drudgery of the lower classes is clealry highlighted who have to scrape hard to get through, and earn money to run their familes.