Just like any other activity. The point of driving would be to put some distance between you and the people who want your stuff. Perhaps you can even cross the border with Canada.
If right now 50% of the population want your money (and get it,) you can expect that number to rise sharply after the SHTF. In absence of law enforcement (or laws,) living among people would be scarier than petting grizzlies in Alaska. The solution to that is in forming communities of like-minded people, with their own laws and the sheriff and the mutual defense force. But you may need to get there on your own. It would be very bad for your health to remain in or close to any city with a large percentage of criminals, whoever they are. Those guys have no option left to them except to rob you and everyone else of everything you have. They can't produce anything; they only can take what other people produced.
I saw a pop chart once, wish I saved the URL.
600 people/square mile where I live.
But I’m only about 20 miles east of Tacoma.
Fair number of like-minded people around me, including some vets and current/ex law enforcement.
If/when SHTF, it’s gonna be rough no matter where you are.