Wrt money - yes £35m is a lot of money.
However, H&M (and other royals) do not enjoy a lifestyle based on their personal fortune.
The lifestyle they enjoy is far in excess of what they could afford as private individuals.
It's not just the money from the sovereign grant, but access to grace and favour houses and security (funded by the taxpayer) plus the connections that allow them to stay (for free) in top hotels or private houses, having friends who will lend their private jet etc.
H&M have cultivated a friendship group of people who are seriously rich. Oprah, Elton, the Clooney's/Beckhams and Serena Williams are worth hundreds of millions.
They can keep up with this lifestyle with the backing the Firm provides but without it their personal wealth isn't going to cut the mustard.
They could live well with what they have but the reality is they have ambitions that exceed their current ability to finance.
Fundamentally that's key to what's happening here. They absolutely have the means to live as independent private individuals but they have champagne aspirations when they can afford sparking water.