There are scores of replies in this thread and they fall into two camps: the outraged and the apologists. The outraged think that it is absurd for a restaurant to buy a flat of nectarines, and then plop them onto plates with just a quick washing as the total value added. They point out that anyone in San Francisco can go to the Farmer's Market and buy their own organic nectarine and cut it up and eat it for a lot less than $4.50. The apologists insist that this is a perfect nectarine, and the essence of California cuisine is that the ingredients are the most important, the cooking is entirely secondary. And besides, Zuni is a CAFE not a Michelin three-star restaurant.
Personally, put me in the outraged camp. Restaurants need to add something or there's just no point in going out. The nectarine should have at least been sliced and served with a sprig of mint or some other garnish. How many people would present such a dessert at a home dinner party, or even a home dinner?
I think high end sushi is the cuisine with the closest affinity to purity of ingredients that California cuisine purists are always preaching. However, no sushi chef would dream of putting anything before the customer without attempting to make certain that the presentation was perfect. Rolling around on a plate is not perfect presentation.
Put me in the apologist camp. I'm so used to paying $8 - $10 for a glass of wine (that the restaurant simply poured) that $4.50 for a fruit seems reasonable. Though one could argue alcohol should be in a class of its own.
A glass of wine is not an equivalent example. No one is expected to do anything to wine - other than serve it in good stemware. (With better stemware being worth a bigger mark-up). Besides, they do take the cork out and pour the wine for you. This nectarine was presented au naturale.