There's a cottage industry in Europe of stealing art that's too famous to be resold. The thieves either sell it to or are contracted to mobsters who want the art as leverage for when they finally get arrested.
BBC art historian Andrew Graham-Dixon discussed this at some length in his 2018 documentary, "Stealing van Gogh." Italy, it seems, has a clause in their legal code that provides for a reduced sentence if you return some of your ill-gotten gains. So Italian mobsters in particular are keen to buy art that's too famous to ever re-sell because in Italia nothing gets such a sizable reduction as a returned priceless master-work or art.
https://www.bbc.co.uk/programmes/b09pqx4r
Interesting, a insurance policy of sorts. He was killing judges and prosecutors, deals might not be forthcoming.