I learned that the ban of selling to under 16's was not against the law, but supermarkets, like Tesco, Sainsburys and Morrison's decided against selling to under 16's due to the high amount of sugar and caffeine, but smaller retailers and outlets could sell at their own discretion.
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Under 16's (As young as possibly 8) do not require energy drinks and even adults have stopped drinking themselves as they have learned that it's not entirely good for them as well.
It's not just the impact on health, but these under 16's may discard their empty cans in play parks and anywhere else, even if there is a bin present.
As a father myself I don't wish my 2 year old daughter to end up being swayed towards an addictive and harmful to health product when she doesn't need this extra energy.