It's funny you say that because I feel the same way as a developer. However, users of my site wanted password-based logins even though I support multiple social logins (Google, FB, Microsoft, etc.). Granted, I use PBKDF2 salting and hashing and I take security seriously, but it's interesting how average people sometimes don't trust social providers or think I'm storing their credentials to that provider.
Let me put it this way. In many (but not all) cases I would much rather Google be responsible for my security rather than some random startup whose primary objective is to stay alive, not take security seriously.