"Reset" button in dialogs

Why is the Reset button, which is all about settings, not on the same line as Load saved settings and Save settings ?

(this appears to be the rule among all such dialogs, I’m not singling out the PNG options)

From the code, it looks like Reset is tied to the GtkDialog’s actual buttons, while Load and Save Settings are additional buttons added to the dialogue.

This explains how, but not really why (or Load/Save should be also part of the GTK buttons).