Liquor is one of the most taxed businesses in the country. A bottle of a particular brand of whisky which cost Rs 400 in one state may cost as much as Rs 1200 in another.
State governments don't want to lose their power to tax liquor business, probably that is the reason why it is still out of preview of GST. It is not only in India, but in a large number of countries across the world, liquor is a heavily taxed business.
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