Dwindling pool of non-members: Facebook is an especially bad example here, because they have enough money and clout to get around this.
How often do you see doctors being hired that are not members of the AMA: Doctors need to be on location, but this restriction doesn't apply to software. Facebook can always find talent in a country that doesn't have an 'AMA.'
More importantly: You don't need to hire only amoral people. You just need enough people with "flexible" enough morals to be able to justify actions that in themselves may not even seem particularly amoral in suitable positions to be able to get certain types of functionality built without having to hand it to the staunch defenders of morality...
In most organisations "everyone" will know who are "difficult" when it comes to dealing with privacy and other issues. Sometimes that means they are the ones you go to, when you e.g. want to be certain everything is right. But if you have something you think is ok but you think they will raise issues with, they will just go to someone more "flexible" in the organisation instead.
Unless the organisational culture itself strictly punishes this kind of behaviour and rewards protecting privacy even in instances were doing so might hurt revenue, there will be plenty of room for amoral people to find each other and "work around" safeguards
Dwindling pool of non-members: Facebook is an especially bad example here, because they have enough money and clout to get around this.
How often do you see doctors being hired that are not members of the AMA: Doctors need to be on location, but this restriction doesn't apply to software. Facebook can always find talent in a country that doesn't have an 'AMA.'