Why does the dope sheet use (inconsistent) white for unselected / deselected? Why does the dope sheet window in Blender uses a solid white color to indicate that a keyframe is not selected and a color (depends on your Blender theme which color e.g. orange) to represent that the keyframe is selected?

I'd like to know why the dope sheet uses the opposite to convention to the 3D view (which uses white to show a selected vertex). It seems inconsistent to me. Knowing why this is should help me to remember whether I have a keyframe selected or not. Currently, I have to remind myself which way round it is by pressing 'A' a few times to select all and deselect all.
It is set that way as they are the colours that were chosen.

You can change both selected and deselected colours in the theme settings if you feel other colours work better. We can't set a transparency with the keyframes but if you set it the same as the background colour then only the border is seen to make it appear hollow. The keyframe border below the keyframe colours is the outline of the marker.