Atticus makes several points to the kids in this speech that suggests the right to privacy for the Radleys. First, he points out that what the Radleys do is their own choice. Next, he makes the kids think about if the tables were turned. He asks how they might feel if he just barged in on them in their rooms without the warning of a knock. He then reminds the kids that if they were to just knock and try to talk to him they just might get a little futher in a civil way. Finally, Atticus says that efforts to communicate with the Radleys must not be through a game that puts their alleged life stories on display for the entire street. Essentially, he asserts that they must stop tormenting Boo Radley with efforts to meet him.
I agree that someone who purposely keeps to themselves does not deserve to be tormented by children. I also agree that if the kids wanted to get to know Boo Radley, they should just go to the door. However, I do understand the childhood fear of the unknown. If Atticus wanted to embody the principles he tried to teach the kids he could walk them over to the Radleys and help make first contact.