Possibly Why Dumbledore Love Chocolate Frogs
As said by Dumbledore, or he said something close to this, "They can take me away as long as they don't take me off the chocolate frogs." As you all know that each frog package comes with a card, and since in the wizard world the cards can talk (I believe) they could be a use of talking between the Order, and it is the Dumbledore card that can do it, since it is so easy to get. Just a thought, what do you think?