wellthatsunusual, it's stange, isn't it. I think sometimes it's because the houses are so big, with space that is, quite frankly, underutilised by the small family who live there, that if money's no object they'll use an interior designer to furnish the place in one fell swoop. This generally means the house doesn't grow organically with the people living in it, they don't buy art and books and furniture 'as and when' they see pieces they like (or even can afford). Everything's just THERE in today's style - that kind of interior is going to date rally quickly too.
If I had oodles of cash and didn't want to decorate my house myself, I'd have someone like Ben Pentreath do it. I think he did Anmer Hall for the Cambridges though so quite possibly outside my budget 
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