So "they" can reach you, even if you don't visit. I guess it will be used to "remind" or notify you of all new posts/entries/content/everything. From there, it can move fast to notifying you about a new sponsor (or just saying who sponsored the new post).

Of course, it will need user approval, so the problem is (I hope) minimized (but just wait for the amount of Google+ "friend invites" notifications you will receive, even if you visited it only once).