Jimmy John's deliver is free and included within the price of the food they are delivering to you as long as you are within the delivery range that they can deliver.
However Jimmy John's does set a minimum order that you must order before they will deliver the food to you.
The current current standing minimum per order, per customer at all Jimmy John's LLC stores, is 1 sandwich ($3.99 for slims, $4.99 for subs, $5.99 for clubs.)
You can order more food if you want too but you must order at least their minimum order for them to be able to deliver.
Otherwise it would not be profitable for them.
It costs money for delivery and actually the cost of delivery for Jimmy John's is factored into the cost of the food.