Yep, all Bitcoiners should be prepared for disaster not just financial disasters. 

kepford

bitcoin

Thought Exercise: What if all you had was your seed phrase?

SatoshiNakanodo

If such disaster will happen, your main concern would not be your 12 word seed for a bitcoin wallet, but:
- shelter, water, food
- security, safe place to go
- anything else will be totally useless

So work better on your "bug out" scenario and be prepared.
- move out from big cities. When something like that happen, big cities are first to fall into chaos. Zombies will kill you on the street for a bottle of water.
- make your house a stronghold
- have prepare food and water for at least 1 month
- diesel generator, batteries, solar etc.
- prepare your "plan B" of escape in case your house is compromised, so have a secondary place where you already stockpiled food, water, defensive weapons.

Bitcoin will not help you at all with all the beheaded chickens out there...