That even applies to books: I've gotten a good number of inquiries from college bookstores asking if instructors can sell copies. They are worried that money is changing hands, when students buy a physical copy, and I am not getting any of it. I am glad those folks are looking out for my rights, but my point here is that "you can't sell it" is a more complex restriction than at least I (in no way a lawyer) thought when I first started doing this.
