Before they were pets, dogs were workers. They can carry their own supplies without complaint (already making them superior to most humans right now), sniff out food and water, and search for and bring down prey. Some breeds, such as huskies, have been specifically tailored to bust their butts on the barest of rations. Dogs also have a long and storied history of offensive and defensive combat use, making them perfectly suited to attack anyone who thinks they have more of a right to that sweet, sweet snack cake stockpile than you do. Which is to say, your four-legged pal is just a few training sessions and a kickass set of armor away from leading you to your rightful place as God Of The Ragged Desert/Water People.
Earthquakes, tornadoes, and hurricanes can cause you to leave your home or even be trapped there. Roads could be blocked due to fallen trees, power lines, or even damaged earth from the natural disaster. Rescue crews can not be in all places at once. You may have to wait it out for quite a while before its over. You won't be able to go to the store or to the corner market.