Interesting, would love to know your use case for this?
If the user is logged out and hitting the route, what do you need the $user object for? As you wouldn't need to know anything about that person - they're anonymous.
auth:api usually means that to access it, you need to provide an API key of some sort - if your route requires information about a user in order to function, then you can't really let anonymous people hit it.
Let me know a bit more about what you're trying to do and i'll try and help.