Well as you wrote it is true that no business can start from scratch dept free since registration of the business and other fees might implicate that you need to put money into a company which has no funds. But if you would seek first for a job, take a pre-payment on your order which you use to establish the business and then pay all the registration and fees, would this mean dept free?
Offering service is easy, besides registration fees you might not have any costs. How about trading? Well if you want to buy goods which you resell you initial require money to do so. Where would the money come from to purchase all your good for trade?
What I want to say, on startup, it requires someone to put money on the table and make it run. Also if you are special in trading it requires much more funds than any service based company. Do you agree?