I agree with the fact that storing your identity on a service like Google isn't necessarily the best idea, but as a developer I DON'T want to be dealing with passwords and account lock outs. OAuth is great in that regard.
So very much this. The reason we're using OAuth in the first place is that we're leaving authentication to the big companies that know how to do it well.
The sheer amount of support work that resetting passwords and fixing access issues (and dealing with hostile actions) generates for a small team is staggering.
