I get the idea, I just prefer the option of a hard-copy compilation book as well. I buy the Privateer Press games updates, even though I could get all the unit cards as I buy figures, and already own all the magazines that describe a decent chunk of the new figures. I bought the Ships of the Fleet books for B5W, despite owning all the source books. I even bought a hard copy of the Epic Armageddon rulebook, despite the fact that a) the PDF is free on the Internet, and b) I haven't played 6mm in a decade or so. I'd buy a copy of Stormwind, too, if they were still available.
My point is, there's a market for compilations. If the market isn't big enough to justify the product, fine, I can live with that. As long as it's been looked at, not just assumed away because "no one would buy that". I would, and I'd imagine PP's sales figures for Superiority say I'm not the only one.