Ages ago, I wrote a post about the art in the show Miss Fisher's Murder Mysteries. The gist of the post is that I am always amazed when I see recognizable paintings used in sets.
The art that you see in sets needs to be "cleared". Often this means one of two things:
1. The art was created for the set, so it is original. No one owns it. Sometimes this art is in the style of a more recognizable artist, but the art was imagined by an employee or contractor of the film.
2. The artist and/or person who owns the art formally gives the project permission to use the image in the set. Getting the rights to use a piece is a hassle and a half, so option 2 is only on the table if it seems "do-able".
That's why I was amazed to see Gustav Klimt's Birch Forest in Wes Anderson's "The Grand Budapest Hotel".
Anderson also prominently places an Egon Schiele painting in his set, but I could not find the exact painting used, so maybe they went with the in-the-style-of option.
I guess I had art on the brain because right after watching Grand Budapest, I noticed a similar art situation in How I Met Your Mother.