Oops, right. I thought the parent comment referred to "double dipping" for hybrid journals (those that have both open-access and closed-access articles): where

Oops, right. I thought the parent comment referred to "double dipping" for hybrid journals (those that have both open-access and closed-access articles): where research institutes pay once for "open-access article processing charges" (to publish) and once more for subscriptions (to read the articles that are closed-access). Of course, all of this is in addition to the intrinsic cost of doing the research.