I see. I guess I just never noticed or bothered to check because at the time I stopped playing base ER all merchant and NPC locations had to be manually marked.
I may be misunderstanding, but It doesn't really seem like that big of a deal to me from what you said. You still need to remember that there once was an NPC at that location, that is now gone, right? And then you have go blindly find them in their new location? All it seems to do is save you a time wasting trip back to their old location, and give you a heads up that they might have moved, if you're especially observant/vigilant in checking your map.
Plus from my experience with Fromsoft games, if I noticed that an NPC was suddenly missing, I wouldn't necessarily think they moved. It's just as likely that I accidentally caused their offscreen death by picking up some random item or killing the next boss or in some other esoteric way.