Hmm, "Jack of Shadows" was written in 1971, which is earlier than I thought.
As to why it's included, well... each of the magicians, once they discover their "place of power", do all they can to establish a stronghold on the location, usually a great big magically-enhanced castle. Jack, being a thief with "non-localized" abilities, spends a lot of time trying to sneak in to these castles and steal magical objects, often at the request (and pay) of other, rival, magicians. It's a setup tailor-made for a D&D campaign. ;)
Plus, Zelazny is an excellent writer! As I said, I recommend anything and everything he's written. :)
s.b. "was", sigh.
I haven't read enough Zelazny, sadly. Just Amber, and Lords of Light, and some of the short stories. I remember really liking the story "Home is the Hangman".
"As to why it's included, well... each of the magicians, once they discover their "place of power", do all they can to establish a stronghold on the location, usually a great big magically-enhanced castle. Jack, being a thief with "non-localized" abilities, spends a lot of time trying to sneak in to these castles and steal magical objects, often at the request (and pay) of other, rival, magicians. It's a setup tailor-made for a D&D campaign. ;)"
That does sound like a good D&D module scenario! Sounds like Jack is a thief/magic-user, too :)