Honestly, if such an event occurs, that in a major portion of the US destroyed nearly every non-hardened electrical device, we would have a lot bigger problems than gasoline.
Picture the Eastern seaboard without a working refrigerator, microwave, oven and stove. Now add in every grocery store unable to refrigerate, sell, or order food. And all restaurants cannot function.
Now add none of the water pumps work.
Would it really be much different than a Zombie Apocalypse at that point?
It would surely be a Zombie Apocalypse. Add to that the death of most people in hospitals.
That is one of the reasons why I am a prepper. My standard of living will still go on if power goes down here.