I remember listening to this episode! I often actually disagree with the host fairly often, but find him worth listening to. I think it doesn't happen because other art museums will refuse to loan works of art to you on visiting exhibits if you sell any of your artwork. The Baltimore Museum of Art (https://www.artnews.com/art-news/news/baltimore-museum-of-ar...) faced a huge backlash when they decided to sell art. Being in the DC area, I do find that I use museums differently when they are free. I can just stop in to see a single exhibit.