Blog productivity

I've been wondering how many blog posts other bloggers write in a day. I usually write 6-8 everyday, with some exceptions of course. I often don't post on Sundays, although it sometimes is hard to keep myself away from blogging. What is it that is so addictive about blogging? Is it just the freedom of saying what we want? Or is it something more? What if no one is reading or 'listening' to our voice? Does that matter at all? Or is the point of blogging, just based on our expressing ourselves, regardless if someone is reading?