Who cares what I care about, the real question is what do my users care about.
It all depends on what users will tolerate in the name of convenience.
It all depends on what users will tolerate in the name of convenience.
So it does come down to what you care about.
I'm saying give people choice, let them figure out what they care about. Making the choice for them is bad business and bad ethics. You don't know better than your users.
The problem is practical; do your users want the features or do they care about privacy? Let them make the choice, and don't hide it from them. That's the ethical behavior.
It's unethical to assume everyone values everything the same, including privacy. Some people don't care about it as much as you do, nor should they.
If you want to argue that privacy is not a right, we can start there.
You can give up your "human rights" for convenience/pleasure as long as you can reassert them down the line.
Signing in via Facebook is also a deliberate choice.
Given a person who wants to jump out of a plane, should it be okay to let them, even though it's a relatively high-risk activity? If the jumper doesn't care, is it ok then?
Given a person who wants to run for national public office, should it be okay for them to release their prior year tax returns, even though it's an exposure of their privacy? If the candidate doesn't care, is it ok then?
Turns out, this isn't an easy game to play, so stop trying to decide for others what they want for themselves. You don't know their situation.