I think a lot of that, for the religious orgs, goes into building massive churches. LDS is insanely wealthy and spares practically no expense in making huge, ornate temples. When they're about to re-dedicate one, us "impure" commonfolk can go inside, and I did that one time and saw some life-size oxen made out of what appeared to be gold surrounding a big ornate pool presumably used for baptisms, and then some expensive looking theaters (practically a multiplex) used for displaying religious propaganda to the public, and practically all of the floors and walls adorned with either granite or marble in pretty much the entire temple, with each room (and there are many rooms) being about two stories in height with really big chandeliers. I guess another way of describing it would be something four times as big, expensive, and decorated as the whitehouse. And in spite of the massive size of this thing, very few people even go inside, and they have about 170 of them throughout the entire US.
I'm a member of the Church of Jesus Christ of Latter-day Saints. We have chapels and temples. You're off on some of your description of our temples. There are 151 temples throughout the world, not 170 in the US. We pay cash for our temples so we do studies to find how to lower costs without lowering quality and workmanship. The White House is approximately 55,000 square feet; approximately 25 temples are at least that large. The largest temple is in Salt Lake City (253,000 square feet); our smallest temple (Colonia Juárez Chihuahua Mexico) has 6,800 square feet. Only a few rooms in each temple have those huge chandeliers and 20+ foot ceilings. Building materials vary. The Provo City Center temple has mostly wood walls, for example.
And for some reason they see fit to ask that their members pay all of the expenses for their own missionary work, even though people of that age typically don't make much at all and it takes them years to save up for that. (My dad was required to save up for it by his parents for about 5 years, and then when he turned 17 he moved away from home and spent it on college and pretty much just ignored the church for the rest of his life.)
There is a standard amount for each missionary based on home country. During my mission, those from the US paid $350 / month while Brazilians paid R$100 / month. There is a general missionary fund available for those unable to pay. All money is pooled together and missionaries get an allowance based on mission. I received about R$100 / month (rent and utilities were paid before I received my allowance). As your dad left the Church at 17, I guess that shows your bias.