Alcoholics have family members, too, but we aren't going to criminalize alcohol.
What's the difference? It takes years of ramping up to become an alcoholic. That's why you don't have many teenagers who are alcoholics. Weed? All it takes is one puff and you are hooked for life.
As someone who was raised by aggressive alcoholics, and I have myself struggled with weed addiction in the past (and seen weed addiction in others), it's really difficult to compare the substances. Yes, weed dependence is bad and people need to be aware of it, but alcohol (and I'd even say nicotine, but that's a different subject) are far more insidious than weed