Have you noticed that most ebooks released by the major publishers sell for $12.99 to $16.99? And ebooks from smaller publishers usually sell for no more than $9.99?
This is because the big--"traditional"--publishers have no desire to sell you ebooks. In fact the only reason they sell ebooks at all is to comply with contract terms they force down the throats of their authors. To get ebook rights they have to publish ebooks. Sort of. But they don't want those ebooks to sell.
Traditional publishers want to publish traditional paper books. And they do. They don't consider it a book if it's not paper. The investment in paper books is considerable. And once they own at least a few thousand copies of a paper book, they need to sell them. If they're selling ebooks, then they're missing paper sales. And, if they're missing paper sales, they might get stuck with books in boxes clogging their expensive warehouse space. BUT they have to offer ebooks to get ebook rights (which is to say, make sure no one else gets the ebook rights).
So here's what they do in that situation: dramatically overcharge for ebooks to force readers to buy their paper books. Worst that can happen: some died-in-the-wool readers spend way more on a file of electrons than it's worth. Best of both worlds, because the royalty the author gets on ebooks is 10 percent of the net amount the publisher receives from a retailer like Amazon.com, about 65 cents on each $12.99 file of electrons.
Readers are screwed, and authors are screwed. That's because, on a level playing field, ebooks will outsell paper books every time.