A decently produced book really appeals to people, in a way that a tablet or phone couldn't.

There's even companies who intentionally publish out-of-copyright books as a way to make money.
Not all of them do it well, but the fact that there's money to be made with it is clearly established.

Somehow, a physical book has more presence than letters on a screen. I don't know if that's just nostalgia from people who grew up with mobile phones or ereaders, but I've always felt more relaxed reading from printed paper.

Personally, I cannot read anything online which take more than two minutes. The whole idea of electronic media is anathema to me. I skip any post on here which cannot be read and digested in one or two minutes. I find that glaring at a screen for prolonged time gives me a headache, and as I have to do it for my job I don't want to do it for pleasure. But give me a good book and I can read for hours.

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Still officially AGA 5d but I play so irregularly these days that I am probably only 3d or 4d over the board (but hopefully still 5d in terms of knowledge, theory and the ability to contribute).

I've actually found that by dimming the brightness to "unusable" levels, I can stand reading from a screen for much longer. I really don't need that much light to be able to read, especially on a high-contrast text such as pitch black on perfect white.

It's still not as pleasant as dead tree format, though.

Most of my go books lately have been Japanese kindle books and the Nihon Kiin e-gobooks. It takes some time to get used to, but it can be very worth it for the convenience factor.