As the saying goes, out of the mouths of babes! One of the purposes for having Scout be a child is so that we can have questions like this. If all of the characrters in the book were adults, no one would question the way the world works. Scout is trying to understand the world around her, and she can't make sense of the hypocrisy.
Scout is expounding her innocent frustration at the duplicity of others. She has not yet evolved to have the double standards which exemplify many adults as shown in the examples cited by others. Her words are of course recorded in retrospect: she is writing as an adult looking back at being a child. I guess the narrator is expecting us to be as uncomfortable as she is with the hypocrisy of others - and sometimes ourselves.
Scout's question points yet again to the hypocrisy of the small town whose Methodist Episcopal Church South sends a missionary and funds to the Mrunas, but does not allow any but white residents in this church, to the "foot-washers" who quote scripture, but malign Miss Maudie, to the gossips like Miss Stephanie who prejudges Atticus Finch.
Clearly, there is a double-standard in Maycomb as in many other places where the immediate is evaluated in a way that differs from the distant whic does not involve any personal risk. While insisting upon respect for adults from Scout is valuable, she deserves an explanation of why people are hypocritcal--brief, however. After all, she is bright enough to recognize it, anyway. Miss Maudie provides the example of how to explain such things when she tells the children about "the foot-washers" and explains some of the quirks of the Radleys.
It's easy to feel sorry for people being abused far away from you. But it's hard to overcome your own prejudices about people you actually see every day.
It's like seeing a picture of some starving person in Africa and feeling sorry for them. Then you walk by a homeless person and you don't help them. It's because what's happening right there where you are is "normal" and you don't recognize it as being a bad thing.
It's all in what you're used to and it's hard to overcome the prejudices that have been built in to you.
I think I'd tell her that and maybe quote to her from the Bible about how easy it is to see the mote (of course Hitler was worse than that) in your brother's eye and miss the beam in your own.
To answer the question generically (not directly to Scout, necessarily) I would have to consider the amazing impact of psychology in this question. For human beings to be distant from an 'ugly' situation, it is easier to criticize and condone that particular situation. But for human beings to be in the midst of an 'ugly' situation, we tend to go with the influences of our peers. After all, it was this knowledge about human behavior that Hitler used in the first place to recruit for the Nazi party.
Kuong, you're a student. Consider it this way: do you think that someone being tortured in a foreign country is wrong? What about a classmate being bullied? When the two situations compared (I know it's not the same, but work with me here for the example) it is much easier to SAY that torture is bad and that you don't stand for it than to ACT on the bullying situation closer to home.
I hope this helps!
If I were an adult talking to Scout at that moment, I would acknowledge that in our house, we don't act that way. Mrs. Gates may have her own sins and convictions that she still has to work through but that doesn't mean a child can call her out on them. She needs to maintain respect for her authority figures in life. So, with taking this look at history, and this look at an example right here in the community, I would encourage her that being "ugly about folks" is not right under any circumstances. Often the things we learn in school give us opportunities to have discussions with our parents at home and in all truth, further moral education happens. The home is indeed the appropriate place for moral education. Scout should be encouraged to think of and treat all people equally.
Scout certainly raises a legitimate point but it is something that is absolutely too widespread. The idea of being a hypocrite is a great one to bring up in discussion and one that some might blow off coming from Scout because she is just a kid and people sometimes dismiss the innocence of children the same way someone might dismiss being cruel and bigoted yet still denouncing Hitler for the same behavior.
Of course Scout isn't the only one disappointed with this type of behavior as her Aunt also eventually flips out at her lady friends for their treatment of the African Americans in their town while trying to drum up aid for Africans.