Remember just say NO to drugs? It failed and will continue to fail as long as there is a demand for people to get high. The consequence to getting high isn't a thought to those who get busted.
Just like crime. No one plots a crime thinking about the consequence of it. It's a utopian mindset that people hold on to and it will never make a difference. Just why people get high, people commit crime for all sorts of reasons with none being "if I get caught how long will I get in trouble"!