Cigarettes, tobacco alternatives, salty snacks, candy, packaged beverages and beer. These are familiar items found at convenience stores, and among the top drivers of sales for those retailers, according to Nielsen. They are easy to grab during quick stops, after filling the gas tank. They must be good for drugstore sales, too, because these are also the products that crowd the front of the stores run by the top drugstore retailers in the U.S. (CVS stopped selling tobacco products in 2014 in order to square its merchandising with its healthcare ambitions; rivals Walgreens and Rite Aid so far have resisted taking that step despite their own moves to offer more clinical services.)