siyan, ... now you explained your question and narrowed down the answer.
Yes, this is done in large cities. ... There is 2 possibilities for this to work.
One. A customer calls a restaurant and places a decent order ($$) and ask it to be delivered. The restaurant doesn't deliver, but tells the customer they have a service that will deliver and the adds fee to do so. The restaurant pays you. But you don't really need a contract with the restaurant; only they know you are available and you delivery fees.
Two. A customer calls you directly and ask you to pickup his prepaid orders (possibly from multiple restaurants) and deliver. The customer pays you.
Now your question: ... The problem that I believe you will have is keeping hot foods hot; cold foods cold; deliver these in an acceptable condition for the customer; and at proper temperature to prevent food borne illness. ... Most likely you & your equipment will still have to be inspected & approved by the local HD. You are working as a type of Catering service.
** However, a $15/$20 delivery fee for a $5 burger is not going to work; except for a Drunk that can't drive.
<message edited by edwmax on Thu, 08/25/11 9:24 PM>