Her post compares per-book costs for pbooks (card catalog info, print-on-demand setup costs) with one-time costs for ebooks (photshop upgrade, eBook studio software). She includes proofing & editing costs as the same for both--which they are, if they're done separately; if both are combined, one of those numbers plummets. I've no idea if a single ISBN covers both a pbook & ebook released at the same time.
And with all that, she tags ebooks as more than $1700 cheaper, per title, to produce than [100] pbooks. The ebook has 70% of the production costs of the pbook... assuming that editing costs are equal for both.
From there, the inequity grows; each pbook sold costs more in print, storage, and shipping; each ebook sold costs none of those. If sold online, both have the same accounting hassles.
Nobody here (as far as I know) is saying "ebooks should be free" or even "ebooks should only cost a dollar." They're saying "ebooks should cost notably less than the hardcover, and probably notably less than a paperback."
The only things keeping the prices high are the ridiculous notions that
- every ebook sold is a hardcover not sold,
- every pirated copy is a hardcover's price stolen,
- honest customers need to pay for the company's lack of security and PR skills.
(Lack of security: Unwillingness to attempt to find & prosecute book pirates--surely if someone were distributing several thousand "stolen" pbooks, they'd try to track the person down. Lack of PR skills: publishers/authors that customers like, are less likely to get ripped off.)