To be fair, she could kind of agree with Frisk. Even though nothing crazy had happened up to this point, that didn't mean things would continue to go that way. And Marinette, for one, preferred to be prepared for the worst. Just in case. Even if it was just her being a little paranoid. "That's right. We'll never know if we don't try," she said. "And hopefully we'll get lucky and it'll just be a regular chest!"