I think there is the attempt to grow this thing until it reaches the point of being self-supporting without any need to be dependent on the voluntary contributions. There is no benefit to a individual to transfer funds to their personal name and be taxed when they have a tax-exempt religious charity with enormous funds to use as their own.
Consider the "charitable" funds created by wealthy sports stars or even politicians (Clintons). The funds coming in are tax free, which is a 30% - 40% bonus (not paid in taxes). Still, as the charity managers, they have the ability to spend it anyway they see fit (as long as it reasonably "justifiable" as charitable -- ie, flying 1st Class to see poverty in South America or Africa).