high turnover are preferred over items with a lower sales rate. The smaller convenience stores typically have few perishable items because it is not economically viable to rotate perishables frequently with a low number of staff. Smaller convenience stores also do not generate the business needed to sustain food spoilage rates typical of grocery stores or supermarkets. As such, products with a long shelf life are the rule, unless a product is specifically aimed at attracting customers on the chance they may buy something profitable, too. Differences from supermarkets Although larger, newer convenience stores may have a wide range of items, the selection is still limited compared to supermarkets, and in many stores only one or two choices are available. Prices in a convenience store are often higher than those at a supermarket, mass merchandise store or auto supply store, as convenience stores order smaller quantities of inventory at higher per-unit prices from wholesalers. Some convenience stores are similar to corner markets, but often have less variety in food. Product containers in a convenience store are often smaller with reduced product quantity to allow more products on the store shelves. This reduces the apparent cost differences between full-size packaging in supermarkets. Reduced packaging also reduces waste when a traveller such as a hotel guest does not want to or cannot carry leftover product with them when they depart. The average U.S. convenience store has a sales area of . New stores average about of sales area and about of non-sales area--a nod to retailers recognising the importance of creating destinations within the store that require additional space--whether coffee islands, food service areas with seating, or financial services kiosks. Convenience stores have expanded their offerings over the last few years, with stores becoming a part-supermarket, restaurant, gas station and even a bank or drug store. In the United States, convenience stores are sometimes the only businesses near an interstate highway exit where drivers can buy any kind of food or drink for miles. Most of the profit margin from these stores comes from beer, liquor and cigarettes. Although those three categories themselves usually yield lower margins per item, the sales volume in them generally compensates for it. Profits per item are much higher on deli items (bags of ice, chicken, etc.), but sales are generally lower. In some countries, convenience stores have longer shopping hours, some being open 24 hours. By