Taking a product such as rice, to the supermarket shelf is a huge challenge involving numerous steps.  To begin, one must develop a supply chain process:  from the farmer to the grain elevator to the raw product dryers and mills to packaging to shipping and distribution, and then on to the retailers.  Growing food, producing food, and then making it into an edible retail commodity is also very expensive! 

Most people do not fully realize how involved this process is and they may take for granted that they can go to the grocery store and find everything there