Why is alcohol measured in ABV instead of the size of an actual measurement, like they do with marijuana products?

Question

Why is alcohol measured in ABV instead of the size of an actual measurement, like they do with marijuana products?

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Answer 1

Alcohol is normally not an ingredient that is added to a product. It is something that forms as part of creating the product. As such it is harder to control an exact amount. They can get a measure of the proof and could calculate back to get a measure of the exact amount of alcohol but it really would be a calculation.

With the pot products you mentioned they are adding pure ingredients into the product so can fairly easily control the exact amount. They add 15 grams of pot to x amount of chocolate to create so many bars with 15mg squares.