It is odd, but not really very inconvenient. It is a piece of paper, much like the other pieces of paper required for the event.
I am mostly just curious to the reasoning. That may be the reason; that usually the cancellation is recent, so the records may not be in order. I thought perhaps they wanted to know because the sealing ceremony may be different, but as far as I can find out, it is not.
In our case, it isn't recent, and the records are in order. Have been for some time. As far as I know, the computer system at the temple is not separate, but a part of the larger church system/records.
Since I know they are in order, and it has been quite a while, why is it even necessary for them to be aware?
btw, thanks to everyone for replying to my post, it is much appreciated.