People want to, and choose to, broadcast what they are doing and who they are doing it with. This shouldn't be news to people. Why do people have public Instagram and Twitter accounts? Some will see no appeal and are turned off by the thought of this, but for others it's their way of life. So instead of criticizing the app, maybe what you really want to do is criticize the people using the app? Lastly, clicking "private" on a post is dead simple; the company shouldn't be forced to change the default setting that differentiates them because somebody can't figure that out. Come on.