Music Education's Catch-22

I had a meeting with an editor from a major publisher today, as happens frequently. They want to know what textbooks I'm looking for, and are polite enough to ask what books I'm planning to write. My esoteric plans don't generally thrill them. But this one asked what kind of textbook I'd like to see. I told her that I'd love a beginning music theory text that isn't so exclusively classically oriented, one that would have examples from Broadway tunes, folk music, and pop music, like maybe some musical examples from the Beatles, so that I can connect the theory to music that my students, of whom only about half are classical musicians, already know. And she told me that, the way things are legally right now, nobody, but NOBODY is allowed to quote Beatles songs in a textbook. She said that her company even published a book on pop music, and were prevented from using a single example from the Beatles. This explains a lot - how can you have a theory textbook that includes pop music if the stuff's all under copyright, and pop musicians won't let you use their work? Thus we end up with all-classical music textbooks. Very interesting. How do we get past this impasse, Sherlock?

UPDATE: Carl Voss writes to inform me that Robert Gauldin's Harmonic Practice in Tonal Music "liberally cites folk, pop, and jazz tunes along with the classical repertoire," including a passage from the Beatles's "Something" to illustrate the use of bVII. I will check, it, out!