It turned out that the frame was made by Anton Kreitzer and that made it more valuable than the painting (which they threw out).
This wasn't the first time Anton Kreitzer was cited in a sitcom. That name happened to be Norm Peterson's nom de travail with his mid-life change of occupation to house painter. He needed to install fear into the lazy painting crew he hired, by making them think Kreitzer was a dictator of a boss. ("Kreitzer" is the maiden name of Norm's wife, Vera. He claimed he chose it because it was the scariest name he could think of.)
I think that after deciding upon "Kreitzer" as the last name, Norm's sub-conscious supplied "Anton" as the first name because he knew of the reputation of the "real" Anton Kreitzer for his frames. Who knows? It could be that Vera Kreitzer Peterson was related to Anton.
So this shout-out to 'Cheers' on 'How I Met Your Mother' could serve as an unofficial link between the two series.