My experience indicates that the few people who do notice can't be bothered to react in any way.
One time I was stopped at traffic lights in a town centre when a guy walked over to the car and looked in and walked back to a couple on the pavement and said something to them most likely that I was naked and nothing else happened.
Got up early this morning and remembered that I had to make my monthly visit to the ATM. So I grabbed my wallet and car keys and walked out to the car nude. As I was leaving I noticed the car needed gas so I drove to the gas station near me that the store closes, but the pumps are left on. I was gassing up the car when another car pulled in. They saw me, but did not say anything. After finishing filling the car I drove to the ATM that is in the parking lot of a local mall. It is a drive up ATM, but I park about 10 feet from it and walk up. I got my monthly spending cash, and headed home kind of disappointed that only 1 person saw me.
Love to drive naked in my RV and sometimes in my SUV. Freedom!
RV's must be the ideal vehicle to drive nude.
High enough that you are not likely to be seen and bathroom and probably snacks and drinks on board so no need to dress if you need any of these.