Why can Xi 'an's Chinese hamburger be cooked by a roadside stall? But the fried dumplings in Shanghai are basically made by renting stores. Why?

They are made in different ways. Fried steamed buns should be fried and kept warm, but it is good to ensure that the meat in the meat folder is hot. Steamed buns are made in advance. But in fact, fried dumplings can also be sold as stalls, but if you sell one pot and then make another, you have to bear the time and cost wasted in the middle.