Why's that? I've seen hotels in Spain with dedicated Tesla parking/charging stations. Gas stations will be retrofitted with charging/swapping options. Tesla/other may partner with other businesses to install charging stations on the street.
Cars will leave while you're hiking to recharge. National Parks may well install charging stations and have regular, automated shuttles running the most popular routes.
Plus you're talking about a very specific case to suggest this being an issue for "large portions of America".
just command the car to go on its own and charge at the nearest charging station while you're enjoying the trail :) This is just one illustration how two tech advancements - self-driving and EV - happening simultaneously would help each other and would result in practical revolution.