Some of it has to do with the perceived righteousness of publishing. A lot of those jobs involve holding people's hands, "emotional labor", like nursing and teaching. These jobs are seen as something people (women, mostly) should do because they like being carers, rather than for the money. These jobs end up being paid less than they are really worth, especially since they often involve many hours without compensation.

That's hardly the only factor here. In the end it's really about the fact that we appear to have an infinite appetite for blowing people up. ($1.5 trillion, next year, a full 50% increase at a time when we're supposedly needing to cut back.)

But don't discount the thumb on the scale against jobs like these. It's a persistent problem in many industries -- so pervasive that it just looks natural.