[yamtaddle]

The large drink size at a major gas station chain around here is about 1.8 liters. It's a popular size. Some people may drink one over multiple days, but that's not the norm. And that's not the largest size any gas stations around here have.

Some "medium" sodas at fast food joints are over a liter, these days.

People who drink a lot of soda, in the US, really DRINK A LOT OF SODA.

Consider also that it's been the norm for years, in the US, to have free refills on soda at restaurants (with waiters eagerly topping them off constantly) and that many fast food places have self-serve soda that's either explicitly or de facto unlimited refill, if you go inside to eat rather than using the drive-through.

[chrisbolt]

"Then there is a horrifying 512oz version that they call 'Child size'. How is this a child size soda?"

"Well, it's roughly the size of a two year old child, if the child were liquefied."