How important is it to note, in a citation, where a book/paper was published? Citation systems often specify writing down the location (e.g. London) that a book/paper was published, how important is this, and if it is important, then why is writing down the publisher/journal name not enough?
I've generally omitted the locations of publishers in the bibliographies that I prepare. (When co-authors assemble the bibliography, I go along with whatever they want, as long as it's consistent.) I haven't (yet) gotten any complaints from editors or publishers about the missing locations.

Looking at the situation as a reader of other people's papers, I don't recall ever being hindered from finding a publication because the publisher's location wasn't given, nor do I remember being helped by the location when it was given.