In the case of cigarettes, making them prohibitively expensive for teens will inevitably curb consumption over the coming decades, even if no adult addict quits because of the tax increase.<p>Tax incentives on the other side absolutely work as well. I have a LEAF parked outside instead of my old Mercedes diesel precisely because the feds and state combined to give me $10K in gov&#x27;t cheese to facilitate the purchase. Sure, I wanted it, but paying $20K was a lot easier to justify and I wouldn&#x27;t have bought it for the &quot;full&quot; $30K.