Soda is sold in 1-liter bottles, and it's usually the same price or even slightly more expensive than 2-liter bottles. Convenience stores and gas stations sell 1-liter bottles in higher volumes than 2-liter bottles because people will accept 1-liter as a single serving (1 kilogram or 2.2 pounds), while 2-liters is too heavy to easily carry in the hand (2 kilograms or 4.4 pounds).