Perhaps for older works which had to be converted by scanning and proofreading them. For example, they got the Perry Rhodan series to ebook by scanning some two thousand issues and checking them. That's some genuine effort, though I still think that charging as much as the current issues is a bit much.
Newer works, hell no. When the text's already in an electronic format, creating a decent usable epub is a trivial matter. (For novels and the like - it's a different matter when there are tables figures or graphics, then you'd actually have to do some tweaking so it works on the most common devices.