Perhaps the answer lies in the way many Brits regard the garden as just another 'room' for the house (when the weather allows). So many folks here like a private area outside, where they can relax without being watched by strangers.
We are a Nation of house buyers in the UK, so we look for a place which gives us what we want... my wife and I wanted plenty of garden because we wanted lawns, seating areas, space for pets and wild areas, so we had to go somewhere we could find all this at a price we could afford... which was why we had to move right away from our home town.
Other people prefer an enclosed and more formal garden, with decking and pools etc, where they can chill without worrying about how fast the grass and hedges are growing.
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