I think that who ever seen a evacuation center and have got the abillity to shelter on his own and/or has pets will choose the hills or something alike.
For example here at Germany you´re not allowed to bring your pets to the evac-shelters and the shelters are underequipped and no more state-of-the-art anymore in nearly all cases, even to the end of the cold war the wheren´t in a better state!

My wife and I we´ve choosen a bug-out-place outside the city in the very rual environment for the case we aren´t able to shelter in place.

Molf