The completist in me loves single-volume “complete works of [author]” books.
The bargain hunter in me loves anthologies that include dozens of stories and hundreds of pages.
The reader in me gets exhausted even looking at books that thick, and goes off to read something else, or play video games.
This dynamic has been true for as long as I’ve been buying books; something like 35 years now.
This is one of the main mechanisms by which I’ve ended up with several hundred unread (or, often, partially read) books on my bookcases.