Can Dominos advertise a delivery deal & then charge for delivery on top?

I ordered dominos pizza (tried to order online but it said my street doesn't exist) %26amp; used the coupon deals for delivery (for example "value pizza $6.95 delivery") with my order totalling $31.95. Then they told me it is $41.95 %26amp; when I queried this was told they charge a $10.00 delivery charge. The deals say for "delivery" So how can they charge on top of that? They had every excuse under the sun %26amp; even the delivery guy said I was wrong!Can Dominos advertise a delivery deal %26amp; then charge for delivery on top?
It states in the fine print that delivery charges may vary.

christian book

pizza deals