Why do recipes call for little or no oil for steam cake?
What will happen if too much oil is used ?
What's a steam cake?
Probably because the moistness in a standard western cake is very much about the fat or oil. In the steamed Chinese cakes, they get plenty of moisture from the cooking method.
There are western cakes that are low oil/fat as well such as Angel Food Cake. It too uses quite a few eggs but adds no oil. OIl would make the steamed cake heavy and dense and not rise properly.