Why a color picker offers almost identical swatches?

Perhaps the first example I met was in Windows many years ago and is still with us:

Pairs of swatches I connected with red line* are nearly indistinguishable. The same in color comb.

         ^{*) freehand[^], yes}

In Windows 10 we can spot similar thing:

But the same can be also found in color samplers outside the software world:

Is there a reason why they are so close in terms of color space? Who can benefit from picking one such a color instead of the other? Isn't this wasting limited space available for color swatches? Is this caused by low attention paid to the final result or is there any meaningful idea behind this I did not notice yet?

Note: I understand that offered color swatches are not distributed evenly in color space in order to promote certain color design, but still some pairs seem to be unreasonably close and that is my question.