That staple mark at the top of the exhibit was probably made by a hand held stapler not punched on a desktop because there is no line of indention from extra force. Then when separated from whatever it was attached to, a staple puller was used to remove the staple because all it left was holes in the paper.
Well, finally, someone else sees the holes I've been asking about since this morning. And there's a large enough pic to see there's probably not an indentation but can't really tell. I haven't bothered to check for measurements either.
Yes, If you didn't attach the pages together, once they were rolled through the roller, they wouldn't match up and your carbon pages would be typed on the wrong lines. It was a royal pain.
However, I don't think that was done in this case. If anything, it was attached to another paper only temporarily because with any passage of time, those staples would leave rust marks. Paper clips from those days also left rust marks in no time which may be why we have plastic coated ones today.