[detaro]

Most of the review and editing isn't done by employees of the publisher, but by other scientists in the field. Sure, the main editors do important work coordinating the process and providing a point of contact, but they get a lot of value from unpaid work in the community. Which they then charge for access.

+ the status of a journal or conference is somewhat self-sustaining, since people want their papers in the best venues they'll submit more/better papers to the venues known as the good ones, which means those venues have a large pool of high-quality submissions to select from, which means they a) can boast high rejection rates and b) have great content, which means they are seen as high-quality, which ...