The comment about J. Grimes Everett is ironic because the ladies care about the Africans but not the poor blacks in their own town.
In Chapter 24, we get a glimpse into the ladies’ missionary circle. These ladies are supposed to be pious, fellow-man-loving Christians.
Mrs. Merriweather played her voice like an organ; every word she said received its full measure: "The poverty... the darkness... the immorality- nobody but J. Grimes Everett knows. You know, when the church gave me that trip to the camp grounds J. Grimes Everett said to me-" (Ch. 24)
While they talk about feeling sorry for Africans, they ignore the plight of their own servants and neighbors who are African descendants. The Africans are far enough away so that the ladies can feel good about being charitable toward them, while they look down at their own blacks.
This is just another instance of the hypocrisy of the people of Maycomb. The women say that someone needs to get out and help Helen Robinson raise her children as Christians, when it is the town that is victimizing the family and took their father away from them in the first place. They can feel good about themselves and pretend to be missionaries, when in reality they ignore poverty in their own backyard.