In 1913 the US income tax was passed. Before that the Federal Gov’t was funded by tariffs, alcohol and tobacco taxes. The ATF enforced these taxes and still does. (firearms taxes too)
"Total Tax Burden: The combined federal and state excise taxes can make up to 50% of the final price at the checkout counter. In some cases, like in the UK, tax can make up a very high percentage of the bottle's cost, especially for cheaper whiskeys."