You don't know that they aren't. The technology and incentive to ensure they are exists, so your assumptions are irresponsible.

[They] store your keys whatever you want to call them, auth is how you get your storage.

Yea, as part of a comprehensive understanding of what you're trying to achieve and how to achieve it, as inferred... That's the opposite of pretending products who's differentiation is privacy marketing are a good thing.