Earlier quoted context omitted.
The padding is there to make the interface cleaner. It forces developers to be more concise with their components as well as making navigation easier for users. Keep in mind Gnome is meant to be easy to use, not easy on the screen real-estate. If you want a minimalist UI, there are a million alternatives in linux land
No, seriously. The padding is just too much, to the level that it wastes space.I know too much clutter is bad, but that doesn't mean GNOME people have to increase the padding to this extent. Can we have a middle ground for padding? Nor too less, nor too much.
sudo apt-get install gnome-color-chooser
Find it in System→Prefs menu after install