[stuhacking]

On the other hand (and I'm slightly playing Devil's advocate here), books and other physical media go out of print eventually. It can become difficult to find a copy of some archaic technical manual that interests you. (Anyone selling any Symbolics manuals? :-))

There is no reason for a digital publishing to stop creating new copies of a digital work (once they finally develop an economic model that works.)

[jokermatt999]

Honestly, I think this is one of the best use cases for piracy. There may be no money in putting out a Symbolics manual, but it costs a pirate uploading a digital version almost nothing. Look at older video game emulation as well. It's probably not worth it to the companies to continue to put out the type of games that wind up on abandonware sites, but thanks to dedicated fans who pirate them, they wind up preserved for future generations.