Which drink is not mentioned as having whipped cream offered on top?

The drink that is not mentioned as having whipped cream offered on top is frappes. This is significant because frappes typically have a thick and creamy texture that may not require the additional topping of whipped cream, as they often contain ice cream or are blended with milk and flavorings that already contribute to a rich mouthfeel.

In contrast, the other options, such as chais, chillers, and Italian sodas, are more likely to have whipped cream as a garnish to enhance the presentation and taste. Chais, usually made with spiced tea and milk, benefit from whipped cream's richness, while chillers and Italian sodas are often served as refreshing drinks where whipped cream adds flavor and a decadent touch. Thus, the absence of whipped cream on frappes sets them apart in this context.