If you look at a US currency note, you will see there are two signatures, the Treasurer of the United States and the Secretary of the Treasury. It isn't unusual for a new signatory to hold up the bill to show his or her signature.
What makes this spectacularly bad form is the image of his wife (with the gloves) who was pictured looking much like this exiting a government jet they used for their private honeymoon in Europe - and she told people, essentially, to get over it. She is the Marie Antoinette of our current administration. See her last instagram kerfuffle below....
