Got to stuff them somewhere. In a year or two, the number of missionaries will drop. But, in the meantime, the number of convert baptisms will rise, but only a little, while the number of convert baptisms per missionary will drop. Diminishing returns. On the other hand, it does not cost the church to do this as long as members consider it a privige to spend their own money (over and above the normal tithing, etc.) to generate new revenue streams for a corporation that spends more on a shopping mall than on people. Got to love it!