I would guess it’s far more common for a publisher to think “but of course I can do my own writing” than to think “but of course I can do my own graphic design”. And then we get the poorly written rules defence here on BGG along the lines of “you know it’s really hard to write consistently clear and correct rules so we shouldn’t expect anyone to actually manage it”. No, it’s really hard only if you don’t have the skill and diligence.
