Try CTRL + L to jump into the location bar (that's if you have a keyboard.)
With regard to middle clicking, I assume you mean a scroll wheel on a mouse. Which some users still don't have! (I know it seems hard to believe.) Also trackpad users need to dupe this functionality somehow, and some haven't picked up on the shortcuts.
Everything else has been replaced either by hardware buttons (back/forward/scrolling/new tab) or by extensions (reload with mouse gestures etc.)
As has already been said the use of the scroll bar especially seems odd to me, I'd have thought middle clicking would have nearly killed it off.