In theory it could be important. In practice the mall will never look like that. Even for something like fat stacks of cash where it went from worthless to very valuable, the price was never nearly that high. Mr. Store stuff could be inflated to artificially high prices by someone sufficiently rich, but they're always priced at > 1m and the mall doesn't show prices of > 1b.
Some time last week, the lowest price for Stunt Nuts was about 100M. At one point, someone put some in their store at about 50k. The mall is a strange place, full of strange happenings.