Why do we have Assemblies? was the topic of the book/brochure study last week.
The answer not presented is that they are the organization's Black Friday.
Stores do Black Friday as a loss leader to get people into the stores to spend money on more pricey stuff, not discounted.
Assemblies are put on to give away books and other literature and have dramas to get people in to donate and contribute more than normally done.
Yes, religion is a business. Imagine if Trump were a religion.