I agree, Laraine. In fact, after carefully re-reading Mr Knightley's rebuke --

"were she prosperous, I could allow much for the occasional prevalence of the ridiculous over the good. Were she a woman of fortune, I would leave every harmless absurdity to take its chance, I would not quarrel with you for any liberties of manner. Were she your equal in situation -- but, Emma, consider how far this is from being the case. She is poor; she has sunk from the comforts she was born to; and, if she live to old age, must probably sink more. Her situation should secure your compassion. It was badly done, indeed! You, whom she had known from an infant, whom she had seen grow up from a period when her notice was an honour, to have you now, in thoughtless spirits, and the pride of the moment, laugh at her, humble her -- and before her niece, too -- and before others, many of whom (certainly some,) would be entirely guided by your treatment of her"

I feel that part of it is relevant not only to that incident on Box Hill, but to Emma's general attitude towards both Miss Bates and Jane -- that their less fortunate situation should secure more of Emma's compassion. Had Miss Bates been a ridiculous but prosperous woman of fortune, if Emma takes the liberty of mocking or laughing at her, she would do so at her own peril -- "every harmless absurdity [would] take its chance". Miss Bates and/or her niece might well strike back at Emma -- pehaps by laughing at Emma's father. The good and the ridiculous is also blended in Mr Woodhouse, and Jane at least must have seen it.

Regarding the obligations between Emma and Jane in general -- Emma did not like Jane and felt that they could never be intimate friends. There had been many earlier posts on this points and about whether Mr Knightley was attempting to "force" a friendship between them. I do not believe Mr Knighltey was being tiresome or pestering Emma to be intimate friends with Jane, although he would be happy if they become good friends. He was trying to remind Emma and guide her as to her social obligations as Emma was the one in a position of social power. Emma did not completely neglect Jane, but she herself was conscious that she was "always doing more than she wished, and less than she ought". Emma only paid Jane enough attention so as not to make her neglect and dislike obvious. Had Jane been an heiress like Emma, or at least in fairly comfortable circumstances, such civilities would have been enough between them. But considering Jane's circumstances, Emma should be more thoughtful and compassionate. Jane was rather reserved, but always polite -- in fact one of Emma's complaints was that Jane was too wrapped in a cloak of politeness. But not everybody has a frank and open temper -- and in contrast to Jane's polite reserve, there is Mrs Elton, whom Emma found ill-bred, pert and vulgar with her over-familiar manners!