Since some users want to close this question as off-topic or opinion
based, I decided to give my own tentative answer, based on my own
thinking since I asked the question, and influenced by some of the comments.
I am well aware of cost issues in publishing, but I have little
experience as a customer where e-books are concerned. Having to fix my
own price as an e-book customer is a new experience to me, and I was
wondering how it is perceived and analyzed by other e-books customers
and sellers. This type of pricing is not usual where paper books are
concerned.
Is this off-topic on this site? I believe not. The topic page states:
The main focus is on the processes involved in publishing and/or
consuming ebooks (and related tools), rather than on the content of
ebooks.
Though this does not explicitly include economic aspects, it does not
rule them out. A question such as pros and cons of publishing in XYZ
format can typically have economic answers.
What is explicitly ruled out is questions about specific books or
sites, or discussing specific ebooks or ereader retailers, when it can
be shopping or opinion based, which does not rule out technical
questions.
My question is about pricing in the general sense, not specific items,
and it is an issue that is seriously analyzed by professionals and
economists. It is a technical and scientific issue.
Many documents do address this issue, for both traditional paper books
and more recently for ebooks.
It is true that many statements are opinion based, because all kinds
of people have an opinion to voice, with or without competence to
justify it (see Consumers Upset and Confused Over E-Book Pricing). Some people have also an interest in keeping this fuzzy,
so that their market is not understood or analyzed too closely, especially by authors and consumers.
My own usual references on books cost are not in English.
However, I was able to find rather quickly some new ones on the web,
such as
Book Cost Analysis – Cost of Physical Book Publishing
which does itself use several external references.
This article agrees that about 50% of the printed book cost comes
from distribution (10%) and retail (40%), to which one can add around
10% of printing costs. This is reduced to nearly nothing in the case
of e-books.
Clearly, ebooks have their own costs, but they are very unlikely to be
comparable to what is being saved (some more than 50%) on the material
aspects of printed books.
What is more likely is that market behavior changes significantly, because eproducts have no marginal cost
(it costs nearly nothing to make extra copies).
That is to be taken into account by both the producers and the
consumers of ebooks. One aspect of it is that the market is a lot more
competitive as more authors can enter it (I am currently reading a
very nice ebook that is available only for free).
Another consequence is that some sellers consider that letting the
customer fix his own price, possibly within limits, is a good way to
do business. Why do they do this? Fixing my own price as a customer,
in a way that is fair, also depends on my understanding of the
economics and of the economic analysis of the seller. There can be, as
always opinion based assessments of it: some people still have strange
opinions about well established scientific facts. But this is clearly
a matter for scientific and technical analysis.
The major point is that paper books both have fixed costs, independent
of the number of books sold, and marginal costs for each (additional)
book. They also have a high investment cost in the printing, since it
must be done in large numbers to be economically acceptable.
The ebooks business has a lesser up-front investment, because no mass
printing is needed, and no marginal costs (the more than 50% in
printing, distribution and retail. Once the book exist in epub, mobi,
or whaterver, it is essentially free for the publisher (except for
advertising possibly, but that is done only when return is expected).
What matters to the publisher is not the number of books sold, but the total
income it brings. Any addtional dollar is worth taking, since what is
given in exchange no longer costs anything.
That is probably the motivations for open pricing and bundle pricing.
Then, I would think that what matters for the producers of ebooks is
not to get a given price for a book or a bundle, but how much of my
money I will input in the book production system every month. Giving
me additional books, that I will probably not read all, cost them
nothing and may increase my inclination to buy.
So my conclusion is that there is no real fair price for each
individual buy. Rather one should spend monthly a global amount
proportional to one's means and one's amount of reading.
The role of the seller is to induce a consumer behavior that will
maximize the total income, rather than the profit per book sold.
One role of the consumer is to make sure the producers can make a
living (and keep producing), which does imply a level of spending, but
not necessarily a high cost per book.
This analysis may not be totally accurate, but it is fairly precise (in a qualitative way) and
can be disputed on objective facts and arguments, rather than opinions.