No one is purely dark or absolute light, just as every race or species cannot be simply one or the other. Even we as humans are as varied and individual as snowflakes in a storm. How not those populating our tales?
As writers we often do fall into this hole, admittedly, and the main reason for this is the confines placed upon us by the length of the narrative. A writer cannot expound on the complications of every race brought forth and still maintain a reasonable word count able to translate into a readable book.
What do we do? We generalise and paint that race there one colour and this species here another hue (excuse the cliche, but you know what I mean!). While this isn’t accurate for all BIG stories, it remains a factor frequently employed.
There are ‘one-colours’ in Lore, yet that relates more to the background histories than to actual character behaviour. The race or two integral to the tales in LORE are as complicated and different as a race should be.
Like us. How not?