Of course they do. The cost of the ingredients is on the order of cents, the marginal cost of labor negligible, and the cost of the machines can be amortized over many thousands of servings.
But even if they didn't, it's a cheap way to get people to show up and potentially order other, higher margin items. If your machine is broken, you lose that funnel and your customers go elsewhere.
But even if they didn't, it's a cheap way to get people to show up and potentially order other, higher margin items. If your machine is broken, you lose that funnel and your customers go elsewhere.