Although these keys are intended to be stored on a keychain, I don't know of anyone that actually uses them that way. If you work remotely, there's just no need to have your keys on you most of the time. One of my keys is a 5C Nano and it just sits in the laptop all day long. So, if my house burns, I'm losing any keys in the house along with it.

As for a fireproof safe, I do have one, but they're rated for X hours and degrade over time. I should probably get a new one.