In the Appearances panel there is: Themes, Widgets, Menus, Theme Options, Background, Header, Editor.
I select Widgets and there are 3 boxes: Available Widgets, Inactive Widgets, and Sidebar. (also 2 Footer boxes that have nothing).
I moved everything that was in the sidebar over to the inactive box, except for one Text widget I added from the available widgets box.
I notice that even though I moved the Search, Tag and Categories Widgets to the unavailable box, they still exist in the available box.
The only thing I see in my Sidebar box is the Text Widget. Yet the others still remain in the sidebar of my site.
Does this answer your question?