Having bad taste in art is hardly a justification of genocide though, so they often need something more. Here we start seeing things that more resemble real world colonial justifications. The orcs, unlike the noble elves, are simply uncivilized. They are brutal and ignorant. They are savage creatures who haven't read any Shakespeare. Well, except for maybe Romeo and Juliet, but everyone has read that. Still not enough Shakespeare to be considered civilized though. Since the good guys always win in the end, and are typically outnumbered, this becomes pretty important. The orcs will brutally, savagely kill a few dozen elves, and the elves will respond in a very civilized fashion by wiping out the entire orc civilization. You can even still see this kind of justification in contemporary colonialism (cough Israel cough).
from the source description
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