Assembly Halls are normally pretty booked up, particularly if they are multi-congregation use as well.
It wouldn't surprise me if this move resulted in the build of more multi-congregation Kingdom Halls/Assembly Halls. They'd pitch it such that it would spread the cost of purchasing land and construction over a larger number of publishers, making it more affordable for users.
Then the WTS would charge them all higher per capita user fees (rent) because the buildings are newer, after all.
The WTS never, ever makes huge changes of this sort unless it has a beneficial impact on their cash flow.
Follow the money, folks. Follow the money.