Addiction is not a character flaw or a lack of moral compass. It's a disease that is inherited and cannot be cured. Getting clean and sober isn't a matter of "growing up", it's a daily struggle that requires support, tough love, treatment programs and complete surrender. If you don't understand why someone is so destructive, it's because you can't understand. If you know someone who was able to get clean, be proud of them every day. Sobriety is a daily struggle in a fight that so many people lose.
To be a little more blunt: If you don't know anything about addiction, keep your mouth shut. You're hurting people by running your mouth about something that you cannot even comprehend.