If/when they do go to streaming and/or pre-recorded media, how long until "conventions" go local? Why not just buy or rent equipment and have it everything at a local kingdom hall?
The assembly halls cost money to operate. The one I went to had permanent staff. Heating/air conditioning & utilities for the living quarters year round, heating/air conditioning & utilities for the weekend of the events, and probably a day +/- for prep/cleanup. Property taxes, building maintenance, etc. Some sort of pay (or just food) for staff.
All of those costs have got to be a lot more than the combined costs of the congregations in the circuit buying/leasing video equipment a couple of times a year. If they hold the events at their own halls, the locals pay the heating & electricity.
They could sell what I'm sure is billions in assembly hall properties around the country.
Although..., don't they charge the congregations for the assemblies? Who pay feeling that it's fair and that they owe something for use of the assembly hall. And this fee could (and probably does) net the WTBS a profit. If everything is local, you can't do that. Unless you charge them for their share of the data streaming fees or for pre-recorded media. But anybody these days knows media costs are dirt cheap and people in IT would know the cost of streaming media servers.