your cute cousin from the countryside grew up
Ooh,, sauce?
I'd imagine it's a difference between zip-a-tone for saving ink and time (or a digital facsimile) and the artist actually being able to use the color concept they actually want. Now, the thing that boggles me is that dark-skinned manga characters almost always look like they've been dipped in pigment
Making a character look like a dark-skinned Negro, in terms of white value, using half-tone dots would look ridiculous, and hide all sorts of facial expressions. It's a limitation of the medium.
And yes, the "bucket fill" problem. Again, it's the half-tone. Carving out a dozen plus small pieces of half-tone to make the darl-skinned character look properly shaded is in direct opposition to the main appeal of half-tone: the convenience.
Also, I would like to thank Hikaru's Scans, the scanlator, for not pushing pronouns on us,
except when the ambiguities of Japanese simply don't translate into English. Some scanlators seem to have a fetish of inserting them into works (or worse changing the original JP text) where no ambiguity was intended by the author.