What religious people mean by “faith” and what faith actually is do not have to be the same thing.
Also, Nietzsche was definitely not confused about what religious people mean by faith. You’re just confused because that quote isn’t a statement about what faith is, but rather, a statement about the psychology of the faithful.
Except that faith has little to nothing to do with social obligations. Faith is believing something without proof or even reason to believe it.
Unless you mean “faith” as in being “faithful” to your spouse, in which case, that’s not even the same thing as what Nietzsche is talking about.