Why did the area codes matter at all? Because they were in seperate books? I imagine you just had a big stack of books on your desk.
We had one computer, very rarely did an actual phone book get taken off the shelf. There issue was we had no local knowledge of the area. So a caller asking for the number of the new dress shop next to the camera shop on Penn Street would be out of luck, unless there was a listing for dress shop on Penn Street, but maybe its address is actually 6th Street, the listing would not show it was actually 6th and Penn.
It is much the same as when you call for tech support and you get an over seas agent that support 30 different companies. They have never seen your product, much less used it. They are seeing what their computer is showing them, no personal knowledge.
As for the unions thing, the operators did not want us to join their union because we were a threat to their jobs, and we were... But not by our own choice.