Probably related to the high prices of delivery services. Maybe people wouldn’t think about financing a pizza if the cost wasn’t tripled by delivery.
I don’t use any delivery service, and I can drive 5 minutes over to Little Caesar’s and get a pizza for about $6, or I can go to Pizza Hut and pick up a better pizza for about $10. But I hear that other people pay vastly higher prices for their unhealthy fast food when they use delivery services.