The closing credits in a full length movie can seemingly go on for ages, or at least 10 minutes or more after the actual film has ended. I realize that modern movies requires a lot of professional people to produce, but why include every single person?
The audience might be interested in the director, producer(s) and actors.
Other movie makers might be interested in finding out who did the beautiful lighting (Director of Photography) and employ them in their next film.
But I have hard time imagining that someone is interested in who the electricians were.
"The light bulbs really worked good." :) Or for that matter Key grip, Best boy and head carpenter.
Bonus question: Have the end credits changed over the years and is there a tendency to cut out "unimportant" people from the end credits in new films? In Sweden, where I live, the TV networks have started to cut the end credits when they air movies to save time I guess. In my opinion it reflects peoples lack of interest in reading the same.