I made that comment in jest. All of those colors exist in the larger box of crayons. Putting them all together and calling it “Colors of the World” is hilarious. This particular box costs over a dollar more than the regular box. Nobody is buying this dumb shit. 
Discussion
What should they call it? It’s not like they call called “BIPOC oppression pack” or “DACA Libre!”
But for the artist, depends on if the task is to draw people. The price may have some marketing baked into it but also likely driven by higher marginal cost of production for a niche color set.
Speaking as a guy who was a fairly developed artist even at the crayon stage - the skin tone pack definitely does have product market fit, albeit a niche one.