@ dexter
If my government wants to build an office building (battleship, bomber, etc.) the project can easily go into the millions or billions. The difference is that the government will throw me in jail if I don't pay my taxes, which can be up to 55% (Fed, State, and Municipal) of your income before you ever see it.
My church on the other hand has a completely voluntary system of offerings. No, I've never been threatened with hell if I don't give 10%. Truth be told, I seldom do; but I'm working on it. There really is no Scriptural reference to back up that threat even if it did happen (and yes, I've checked).
Also, when a church is built it's a voluntary project funded for the most part by the congregation. In most cases they take out a loan and repay it themselves. In at least one case, that I know of, one individual came forward and funded the entire building himself. So really, no matter how big and expensive a church is it's usually voluntarily funded by people who worship there. Something the government never attempts (and indeed couldn't do).
Certainly there is little reason to point at "elaborate and expensive churches" that for the most part were the product of hard work and savings of local congregations, as evidence of greed on the part of the international institutions themselves.