People will pay crazy amounts for archival prints.
Also, it's Hardcover, 632 pages, in cardboard box with handle.
Krazy Kat represented a turning point for comic strips. Once it hit the newspapers, it made comics "art" (whatever that means to people). So it's a huge book with a good comic that plays on nostalgia or historical importance. Deadly combination for selling it for so much.
To compare, the complete Calvin & Hobbes hardbound collection is $300.00… but you can find it all over the place for almost half that. So I assume this collection will be the same way.