OER use by commercial publishers

I just read a very interesting article from “Inside Higher Ed” on the recent upsurge in use of OER by commercial publishers. It’s also the topic of a new guide by longtime OER advocates ISKME, titled “Toward a Sustainable OER Ecosystem: The Case for OER Stewardship“.
By open licensing their creations, OER authors (mostly — see this discussion of the “Noncommercial” Creative Commons feature) leave the door open to commercial use of that resource that the authors clearly intended to be used for free by faculty and students. Commercial use would seem to contradict that intention. The authors of the new ISKME guide began the work of clarifying when commercial use would seem to be in accord with the author’s intentions (such as creation of an online homework system based on and in support of the open licensed content), and when that use would tend to be in bad faith. Take a look at the guide and please comment your thoughts on this important issue.