An apple isn't the best analogy since the apple market is competitive. The market for "Principles of Economics: Global Financial Crisis Edition, 6th Edition" (or any other book or ebook) is a government-granted monopoly, so the two situations aren't completely comparable
This is my own personal belief, but my main objection to ebook pricing is the apparent price collusion that is going on in the publishing market (here's a link to a news story about one DOJ case: http://www.politico.com/news/stories/0412/75028.html). This isn't the first time that a format change prompted increased prices: when the CD was introduced, music labels charged much higher prices for CDs than prior formats -- notably, all of the labels also seemed to converge on a single, higher price. Arguably, the higher price was justifed due to better audio fidelity; maybe the same could be said for ebooks' features vs dead tree books. For at least a decade $20 CDs were the norm despite much lower music prices in the cassette era and much lower prices now. Check out Knopper's 'Appetite for Self-Destruction' or Kernfeld's 'Pop Song Piracy' if you're interested in the music industry specifically.
To cut it short: in a government-granted monopolized market, it seems a bit fishy when the entire market lurches in the (same) higher priced direction simultaneously.
You are completely wrong about CD prices. They were cheaper than tapes and records to make up for the "relatively" high cost of CD players. Back then an entry level CD player cost about 250 USD but a tape player could be had for about ten dollars. The cost of printing CD's was therefore subsidized to encourage adoption of the format.
This is my own personal belief, but my main objection to ebook pricing is the apparent price collusion that is going on in the publishing market (here's a link to a news story about one DOJ case: http://www.politico.com/news/stories/0412/75028.html). This isn't the first time that a format change prompted increased prices: when the CD was introduced, music labels charged much higher prices for CDs than prior formats -- notably, all of the labels also seemed to converge on a single, higher price. Arguably, the higher price was justifed due to better audio fidelity; maybe the same could be said for ebooks' features vs dead tree books. For at least a decade $20 CDs were the norm despite much lower music prices in the cassette era and much lower prices now. Check out Knopper's 'Appetite for Self-Destruction' or Kernfeld's 'Pop Song Piracy' if you're interested in the music industry specifically.
To cut it short: in a government-granted monopolized market, it seems a bit fishy when the entire market lurches in the (same) higher priced direction simultaneously.