The products and types of customers may vary depending on the industry, but, besides that, the duties and responsibilities for Store Assistants are the same in all industries. We researched a plethora of Store Assistant job descriptions to come up with the following list of Store Assistant duties and responsibilities.,Store Assistants also help stock clerks process and receive shipments. They use stock scanning guns and inventory software to check in each box, and then they put it in the stock room neatly.