Comment 3 for bug 1098596

This is because we are seeing several different icon themes in that window.
"Details" & "Universal Access" - from Humanity.
* "Landscape Management" - from Landscape client.
* "Privacy" & "Time & Date" - from Gnome Icon theme

While one could argue that all the icons could be created and included in Humanity, this is not likely to happen. With the prospects/rumours of a new icon-theme/design style for the default Ubuntu, Humanity development has not made progress and it is less likely for new icons to be created. Humanity is currently in maintenance-only mode for major issues which break the OS.