In to kill a mockingbird Why is Scout afraid to play the Boo Radley game?

The fear of Boo Radley is built up throughout the first few chapters of the book as everyone tells some kind of story of a run-in with him or even just being on the wrong end of something he supposedly did. The fact that he never leaves the house only serves to reinforce all the stories. Though the other kids think that her fear stems mainly from a fear of Boo Radley himself, Scout makes it very clear that she thinks the main problem is that Atticus knows about the game and she is not comfortable with that knowledge. Scout feels that Atticus will not approve of the game, even though she can't quite articulate why