Colour!

[Lolsworth]

You know what? The fact that no-one has a nose is somehow oddly more unsettling in colour.

[John T]

My theory is that, with everything neatly separated by flat color, it's easier to pick apart the flaws of each section. The art is no longer just a jumble of lines. Thus, you pay more attention to the individual artwork in the "peach" sections and notice that the noses are missing.