I mean simply that E-Ink (EPDs) remains incredibly patent incumbered, and the primary holder does not sell screens cheaply.
Your format and incredibly late reply make me think you're asking some sort of "Gotcha" question here, and I have no idea why.
see:
About E Ink
E Ink is the recognized leader and innovator in electronic ink technology, with over 600 U.S. patents, and 1,374 worldwide patents. E Ink continues to aggressively fund and place corporate priority on innovation, invention, and the *defense of its extensive intellectual property holdings*.
E Ink Corporation was spun out from MIT’s Media Lab in 1997 to commercialize electronic ink and electronic paper display (EPD) technology. In 2009, E Ink Corporation was purchased by Prime View International (PVI), a leading small and medium sized TFT-LCD and EPD provider. PVI was later renamed E Ink Holdings, Inc.
E Ink Holdings Inc. (8069.TWO) is now the world's largest supplier of EPD displays to the eReader market. It has transformed and defined the eReader market and is redefining the signage, architecture and design, mobile, wearable and retail markets with its ePaper technology, enabling a new multi-billion dollar market in less than 10 years. Its corporate philosophy aims to deliver revolutionary products, user experiences, and environmental benefits through advanced technology development. This vision has led to its continuous investments in the field of ePaper displays as well as expanding the use of its technologies into a number of other markets and applications, including smart packaging and fashion. Its EPD products make it the worldwide leader for ePaper. Its Fringe Field Switching (FFS) technologies are a standard for high-end LCD displays and have been licensed to all major liquid crystal display makers in the world. E Ink Holdings is listed in Taiwan's Taipei Exchange (TPEx) and the Luxembourg market. For more information please visit www.eink.com.
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Edit - I see from your other replies this is clearly intended as a "gotcha" question, but I think you're incorrect in your assumption that volume is the problem. I'd argue that much like 3d printing, the issue is not really costs, but rather patents and licensing... as I clearly alluded to above.
For comparison, Amazon alone is shipping 20+ million EPD products a year through kindles. Most LCD TV manufacturers ship around the same volume, and the industry total is only around 200 million. see: https://www.statista.com/statistics/668519/lcd-tv-shipments-...
Basically - I'm claiming your argument is bullshit. The cost difference is driven by IP protections, not by volume of sales.