There is a take-away pizza place, that shalt remain nameless, on the Caledonian Road, London, which advertises 'FREE DELIVERY', on it's leaflets.
On the back of the same leaflet, there is a section that says 'SPECIAL COLLECTION ONLY PRICES'. These prices are about four quid cheaper than the regular prices on the leaflet.
In other words, if they deliver the pizza, it costs more than if you go in and collect it.
If the price of a pizza is 12 pounds, and the delivery is free, then how can the same pizza be 8 pounds if you come in and collect it? Surely that means that the delivery costs 4 pounds, and is not free?