Punishment and intimidation, no doubt. But, I suspect something even more sinister. Once those of faith are driven from TEC, then they can swell their ranks with secular humanists including a large proportion of homosexual clergy and members. No single demonination currently bills itself as the Homosexual Church, but this seems the direction that they are going, and they certainly don't want to have to start from scratch building congregations and acquiring property.
Why are they fighting so hard for the buildings, even if they are empty?
Elementary! Buildings and real property are WEALTH!
And what is the perfect situation for these guys? A situation where every dissenting voice is excluded from the "church", so that all that is left is themselves and their cronies, and they control all of the wealth. Then they can liquidate it, as its trustees. Naturally they are the ones in charge of deciding their own salaries, retirements, perquisites. They answer to noone.
The ideal circumstance, if you want to get very, very rich, is to be an uber-gay, uber liberal Episcopalian clergyman in charge of a parish where you have empty buildings and nobody in the pews. Then you liquidate the parish and find yourself as the trustee of all of that money, to which your hierarchical position gives you command, and none of the formal faithful have any recourse. And then being an Episcopalian clergyman is the best gig in the world: a MASSIVE endowment with full tax exemption, no pastoral duties, and the theological right (according to YOU, because you are not answerable to anyone) to have gay bondage orgies in the grandest rectories in the districts, there being nothing else left to do after all, and nobody to answer to.
If you don't believe in God but DO believe in money, you are in the best position of all to get control of a really ornate, beautiful building on a piece of prime property, completely devoid of worshippers or anyone else to answer to other than your own fellow perverts.
Do you really think these guys even believe in God at all?
It's laughable.
They are mercenary civilians who have found a neat legal trick to acquire a bunch of property and treat themselves to the high, gay lifestyle with nobody above them, and with full IRS tax exemptions. What a gig!