The country I live in has international schools which teach in English. You can relocate here and use those schools, if you really want.
But they're extremely expensive, and academically speaking do not deliver the standards of a top London private/super-selective grammar school (I don't mean they are bad schools, but probably the academic attainment level will be no better than that of a good state school in the UK, rather than St Pauls Girls School or what have you). That's because
a) They can't be as selective, as they have to select from a much narrower pool of applicants. Expats' kids vary quite a lot and are not all super bright
b) Staff and pupils come and go quite a lot, making it very hard to have any accountability for results.
c) Kids come in from other countries' systems, from the local school system, and from families which don't speak English at home, and this means that schools must spend time and resources working with some of the kids to fill in curriculum/knowledge gaps, gaps in their English, or both.
Then you have got all the complications of living overseas. Even for the wealthy, it's not always easy. With both men and women having careers these days, it's hard to find locations where both halves of the couple can prosper. More and more people come from small families with one or zero siblings, so there is concern and guilt about leaving elderly parents behind. Relocating always involves far more costs than anyone estimates at the time they make the decision. Don't even get me started on the growing cost of international flights. Companies are less generous than ever with their expat packages, not least because the growth of English competancy in much of the world means there is less demand for western expats unless they really are fluent in the target language of the country. Contrary to what a lot of people seem to think, many of the forces at foot in the modern world are making international relocation harder, not easier.
I really cannot imagine the large majority of rich people engaging in all this bollocks JUST in order to avoid VAT on schools, seriously.
I'm basing this on experience as a long term resident in another country with many expat friends. I don't consider myself an expat, and we've used local schools (a mixture of public and private), fwiw!
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