Yea it's a bit of that but...
In all honesty Rob told me he had zero interest in using American printers because Chinese printers were cheaper. So he doesn't even gather quotes from Americans.
At the time told me this, I considered what it would cost my company to print Erfworld Book 2 in a comic book form (Zine style). Using very nice paper stocks, a Heidelberg all-in-one (even makes its own print plates) 6 color printer, A 6 step program on the Polaris guillotine cutter, and then a Horizon all-in-one auto-stitcher (it folds and stitches and does final trim) I got the cost down to, if memory serves, 4 dollars a book at less than 1000, and 1 dollar a book over 5000, with a 72 hour turnover from final artwork to shipped to customer. I did that just for myself to know, I never asked Rob what he was paying the Chinese.' (for reference: 3 machines, 50 hours of labor and machine run time)
Hardbound books would have depended entirely on the cover material, and about a $1 per book increase to fold for the perfect binder instead of flat sheets on the Horizon. Perfect binding for us was only about a $0.25 difference over the Horizon because of glue. So it would have cost us 5.25 (plus price of hard cover material) to make the hardbound books at the 1000 books price.
And the company I was working for at that time did and still does comic books for DARK HORSE.