Look at these two screenshots carefully. Look below at the static text in the footer and right above the footer. Notice that the font and spacing change. A visitor has different style and size, and when the user logs in, it looks different.
On my website, it is very noticeable. The site looks much better when logged in vs. when a new visitor is there.
As an update, I have tested this on the latest versions of Firefox, Chrome, and Safari. Logged in user sees the font and spacing closer, and more clear.
Visitor sees wider, bigger fonts (slight).