Do not worry about the food stall early in the game. Although it can help you earn money, it requires a lot of investment. You will need to purchase the stall as well as buy and build another trader's house. Furthermore, in order to have anything valuable to sell you will have to learn cooking recipes which also require money. It will take some time for you to get a return on your investment. If you need immediate money, it is not a good way to obtain it.