Did the Brexit virus remove many people's brains? So where is the economic reasoning behind having both a 500 ml and a 568 ml package? Haven't people heard of

Did the Brexit virus remove many people's brains? So where is the economic reasoning behind having both a 500 ml and a 568 ml package? Haven't people heard of the term 'Economies of Scale'? Pick one size and stick to it. And it would be better to pick the size that has more export potential. Like it or not the Metric System has taken over the world. Many billions of people in the World know what 500 ml is, only a few hundred million people know what 'a pint' is.