My preference would be to share everything publicly, but to do that I have to come to this interface and do it manually.
The Google+ API does not allow external apps to share anything to Public, it will always just be to Friends. And Google+ does not allow you to edit the sharing parameters after the fact.
"Delete it and re-post it!" they happily say.
I would love to post through Flipboard, and then pop in to catch the engagements. But it is damned frustrating to insist that I log specifically into the site and manually do what I can do elsewhere with a bookmarklet?