Plastic bags can be used for everything from bagging groceries to storing ice or food to storing nuts and bolts. Plastic bags keep food fresher by sealing out the germs. Millions of plastic produce bags are used each year to put fresh fruit and vegetables in grocery stores. Plastic Thank You bags are used for takeout at virtually every restaurant in America now. These are the plastic smiley face bags you get for to-go orders. Let's not forget about ziploc bags, the top selling plastic bag brand in the world, used to seal food for freshness.