What does Doolittle actually want from Higgins and what explanation does he finally give for why he deserves it? (Act 2)

Higgins, seeing that Alfred has brought his daughter her luggage, asks him why he would do that if he wanted to bring Liza back home. In not too subtle language, Alfred says that he does not mind if Liza becomes Higgins's prostitute so long as he gets some money out of it, too. He asks for five pounds. He adds that his life is very hard because he is one of the "undeserving poor."