Because you can?. . . Why hang something on your wall when someone else is crazy and wealthy enough to pay 30.000$ for it?
"We have decided to keep the photo in our family"
... I would have sold the original and kept a copy. Why hang something on your wall when someone else is crazy and wealthy enough to pay 30.000$ for it?
Or... um... why not enjoy it themselves? Why put up with an inferior copy? I mean, why not give away today's dinner and eat a McDo instead?. . . If they can afford 'not having to sell it,' why not let others enjoy it for a few years.