What's the pyramid scheme here? The Netherlands are the top producers of tulips today, seems like a sustainable business. A temporary inefficiency in markets does not make a pyramid scheme.
Selling tulips is a fine business. Selling tulips at an insanely high price by promising that the market for tulips will keep on expanding and increasing the price of tulips is a pyramid scheme. (Well, maybe not quite a pyramid scheme, the structure isn't right. But it certainly wasn't a sustainable business model.)