They start with the Bible. Now, take "things that really exist and have a well-evidenced naturalistic explanation" and see if they contradict the Bible. If they do, then invoke magic. If they don't, then thank god (or whatever). Now, take something the Bible says really exists but for which we do not have a well-evidenced naturalistic explanation. If the audience is fellow Bible believers, then nobody cares about a natural explanation. But if your audience is scientists, then you'll need to come up with a natural explanation if you want them to consider that the Bible was correct in saying that the thing really happened.
Creationists do
really really seem to care that the physical evidence doesn't contradict the flood though. Not just with scientists but for their own internal reasons. No?
But they don't care that physical evidence suggests that turning wine into water, or rising from the dead is kinda unrealistic.
What do you think they see the difference as?