In my observation, in international markets the price of a McDonald's soft-cone dessert is 1/6th of their primary burger ! Source (for example): https://menuprice.co/in/mcdonalds-menu . The pricing is simply unsustainable if folks walk in only to purchase the soft-cone. The clever marketing folks understand this underlying 'loss-leader' dynamic. The consumers would not tell you this explicitly - as it would appear to be 'cheap' on their part, but consider it a good-deal whenever the 'McFlurry' machines work. Further it has been shown sugar is pretty addictive.