> I also couldn't just walk down the street to get a pizza.

Well, not necessarily. Jensen Huang was famous for going to random food stalls in Taiwan and eating street food.

It might be harder and riskier, and I get what you mean, but it's not like you actually can't do those things.

Also maybe it's not necessarily a billionaire thing, but more like a fame thing. Billionaires tend to get famous just due to being rich, but I'd imagine a random person wouldn't recognize 80+% of the people on the billionaire list if they saw the billionaire chomping down a pizza in the local pizza place.