The MSRP of a book, including ebook, is clearly not related to production cost but rather to what the market will bear. Costs will rise to meet the incoming revenue, because that's what costs do, with the help of boondoggles, tours, marketing campaigns, unions, etc. Some do, some don't apply to books, but that's how it works. EBooks are still trying to find their resting point.
There's a chain department store out here, Fred Meyer, that often has at release the newest blockbuster movie on DVD for $9.99 - $11.99. This is typically nearly two hours plus another hour of "extras", the extras being the only bit you don't get for incremental-cost free from your Dish-PVR, HBO or NetFlix streaming. The soundtrack for that movie, which has
less material (the same music and none of the action/video/etc), running at typically 50 minutes, so about 1/4 the total DVD length, is priced at $17.99. So you pay nearly double for a lot less material... but part of it is because the availability is artificially less than for the movie - HBO isn't streaming the album specifically.
Is anyone here going to argue that the CD soundtrack really has higher costs, of any sort, than the movie DVD featuring the same tracks and more?
The music market is changing though. For example, the Adele album "21" would almost certainly have been $15.99 on CD if released three years ago. Amazon has the CD for $9.99, but the digital album costs a dollar more
despite obviously having lower manufacture costs, and the a la carte tracks would add up to about $15. And publishers are reducing the prices of older albums by "remastering" them into $8 CDs.
Magazines point out the fallacy of book prices too. Magazines also require editing and production, on a tighter timeline and with a far shorter payback timeframe, but cost less.
The publishers are trying to find the pain point where the trade offs between the formats, the ease of pirating books (including ebooks, but also in someone doing a scan/OCR/publish) and prestige (the initial hard cover will probably always be an "event") and the loss of sales to lower-priced competition (do I really care about this $12 ebook when I can buy four other ebooks that look entertaining for the same amount) equalize. But it won't have anything to do with production cost.
<This long message had essentially zero production cost.

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