"If you drink bad homemade alcohol, it may have methanol, which is deadly. It can cause vomiting and blurred vision, and ultimately, can kill you. The cure for methanol poison is drinking ethanol, regular alcohol. So basically, if you get sick from moonshine, drinking good whisky or vodka can save your life."
F@#k, man. Thanks for that, I guess....
But during prohibition, the US government mixed it in to try and make people not drink moonshine or spirit smuggled into the country.
Now criminals might mix it into the spirits of other criminal gangs smuggling in contraband spirits.....