There are business costs and administrative costs whenever this type of malarkey happens.. Websites have to be changed, maps, what a JOKE!
Yes, all their correspondence documentations (including business cards) have to change.
Of course, sometimes they can rather easily “paste over” the old with a few prints ready to go when needed.
MD sure didn’t care when they made most of us (except dear ol’ DC counties) change area codes AND have to use them for locals 30 years ago.