Once the Queen passes, the Schacks won't be able to leave Denmark fast enough, and permanently, mark my words. Joachim will have a big fat inheritance and he won't need the apanage. Or perhaps I should say he'll sacrifice the apanage for his freedom.
I don't have anything against them but it kind of bothers me that these "spares" can't find their niche in their own countries. And maybe contribute a bit more to their homeland. That's probably too much said so I'll shut up now
IMO, they want their kids to be fluent in French and have both cultures. And they want a temporary good job to boost Joke's carrier. It helps Denmark too, to have a high rank military trained by French Army, as Joke said it during an interview. This French "Ecole de guerre" were he was trained is really excellent, and French generls are very often leading peace operations around the world. French diplomacy is probably still number 1 (it's a French word) and except Apostolic emissaries from the Holly Sea, first diplomats were French. French are still all over the world. They are neighbors of many people on this planet. They have militaries watching over their oversea's territories. Joke said he wanted to learn and share his experience later in Denmark, so he will return to his homeland. As he is half French, he had more easily access to this school, carrier. French consider him as French. His family name is French, to begin with. And he has a land there, his family owns their estate, and they employ people. They pay their taxes, too.
Their children are 75 % French, I think that they were speaking French at home in Denmark, so they could be fluent. This years in Paris will definitively help them to progress.