-- what the other posters said --

plus a fuel efficient sedan is likely to be able to travel further. So when your 4x4 bogs down after 250 miles because you ran out of gas, your neighbor is thumbin' his nose at you as he drives past you. Better hope you have all your gear in a good tote bag or backpack because you're now walking to the next town and you still might not be out of range of the next hurricane.