Smaller bags of potato chips and drinks that do not have Pepsi printed on them are helping push up PepsiCo’s sales. PepsiCo Inc. said Tuesday that snack volume in North America rose by 0.5 percent for the third quarter, while pricing pushed up sales for the division by 2 percent. The maker of Frito-Lay chips has been increasing options on sizes, offering Lay’s potato chips in a bag that is two ounces smaller than the traditional 10-ounce bag. Tom Greco, the head of Frito-Lay North America said last month that the company is shaking up bag sizes because of shrinking U.S. households, but also to improve margins for retailers. More