If an illustrator is paid for their work, can their name be shown when the work is published?

The obvious answer to this question might be yes - at least if the illustrator asks for their name to be shown, as part of the contract for providing the image. Often, illustrators are not formally mentioned, but can at least put their signature, and a date, inside the illustration.

Where I work, it is accepted that photographers should have their name shown next to their photograph, even if they do no ask for it.

But for illustrators it is opposite it seems: we should not show the name of the illustrator!

And the same for translators, we should not show the names of translators employed for translation jobs. Supposedly acknowledging hem gives them an unfair advantage compared to other possible future translators; they do not have a recognised, auomatic right to be acknowledged for heir intellectual contribution.

Yet we should show the name of the printing company that printed our publication, even though that is merely a technical and commercial contribution.

I don't understand these different standards for different kinds of intellectual and technical input to a publication. Shouldn't the process of intellectual production acknowledge all significant sources?

As a researcher, I expect to have my name on the papers I publish, despite the fact that I am paid by contract to do the work. Why should this be different for other contributors to the process of scientific communication?!

What experiences do others have of this kind of mixed, inconsistent approach to acknowledging contributions?