In a lot (most?) of the US most places are far enough away from each other that using a shop's car park as somewhere to leave your car (e.g. while commuting) does not happen. There is also no viable public transport.

Charging for parking, then, is nonsensical. It's a cost imposed on your business just like the rent.

You could try to recover your rent/land costs by charging a flat fee for people to enter your shop on foot. Why not? Well, because no-one will come any more.