30% is totally reasonable for the cost of delivery. As you point out people hate paying for delivery in spite of the marked increase in cost/service. Where things get complicated here is that a lot of takeout services will require businesses to offer items at the same price given to pickup/takeout orders. This constrains the restaurant's pricing while providing a large benefit to the delivery service. If the restaurant could just charge 30% more for people using the delivery service then fine. Instead they need to either make take out customers pay more which usually means making your neighbors and long term customers pay more to subsidize a large well funded company.