Mary does not like Dr Grant.. I think she knows she's nto suitable to be a parson's wife, but also she does not greatly like clergymen. She thinks that a clergyman is not and can't be "fashionable" and that he can't be a leader of the ton... so she's not interested. and she thinks that many take up the profession becuase its an easy job. and no doubt she also thinks that clergy are often hypocritical.. so there are reasons why she would not wish to marry one. But for most women, a clergyman with a good living would be a very good catch. and for Augusta Hawksin wiht her dubious background in trade, her relatively small fortune and probalby she's getting a bit long in the tooth, Mr E is a "godsend"