A principle out of 'The Communist Manifesto': That a rich person leaving the communist society is stripped of his wealth as he leaves.
Corollary to that: That rich outsiders are not permitted to profit off of the communist society.
France has so far failed to apply that principle on its exiles. I haven't seen them apply the corollary either. Will they stop showings of G. Depardieu's films, or require that he not be paid anything for future showings of his films in France? Etc., etc..
What Marx did not appreciate is that most of those guys' wealth is in their skills, not in their possessions. And thinking that they could be forced to work, w/o reward.