Easy. Voting is meaningless, but exists as a pressure release valve for society's frustrations. Every few years, you're expected to go to a booth, throw a piece of paper into a black-hole, and then blame everyone else around you for things none of you have ever controlled. Drinking is a release valve too, and a very profitable one. It's profitability is maximized by denying it to you for the first 2 decades of your life, until it becomes a forbidden fruit that you're grateful to indulge in.