We received a Christmas postcard. It was the front of a Christmas card. I wouldn't have known except the back was torn off & part of the fold of the card was showing. If you cut them neatly, nobody will ever know. Hmmmm - 27 cents postage too.
I save Christmas cards to make little boxes to put gift cards in. How many of those do you need? Now they will be recycled.
My Mom uses the front of the card as a gift tag.