Is this art or thievery?
You have to admire the sheer audacity, and it has long be held that Tracy Emin's definition that anything created by an artist IS art.
Though this was not the art this particular artist was commissioned to make, my guess is that at some point the money will be returned and the name and reputation of Jens Haaning will have been made, and his two empty frames will have become salable piece of art in their own right, thanks to the story worth far more than the cash he was loaned.
It's a crazy world we live in.
No. Theft. They commissioned specific works of art that were supposed to contain the bills. So not only did he steal the art supplies, he shouldn't be paid his fee as he didn't fulfill his end of the contract.