Yes because the government would want Facebook to store user passwords. But only some of them, specifically facebook lite users, you know, the users that can't even afford a modern phone and reasonable internet. And they would want to use the passwords directly, instead of having some other backdoor for getting data from these accounts, so that way the users they spy on can see that they're being spied on because of the suspicious logins using their password. You've cracked the case =)