My father told me that my grand parent used to cut Coke with carbonated water when it first appeared in Argentina because of two reasons 1- it was very sweet and the people wasn't used to that. 2- because it was very expensive.

He said that the 750ml bottle was enough for the 4 member family, one glass per person. When the 1L bottle came out, it was a problem they didn't know how to hand out the remaining, so they decide to have another child, my uncle.