GAMER LOUNGE 20XX (NO CASUALS!!)

[TomGuycott]

I've always seen them as mouths, mainly because the character design in the series has never really had immensely pronounced noses for most of the characters.

I assume they did it that way because if the sprites remained exactly as they are, but just swapped out that colored line for black, they would look like they have a big blob of black on their faces and look slightly weird.