The worrying part here is, if this is a reflection of the population at large. What must this be costing in terms of health care and the social issues? What’s this costing where marijuana is legal?
Why exactly does it worry you if people smoke weed? What are the health care and social issues you're concerned about?
I smoke weed almost every single day and have a job where a lot of business money is on the line and there's never once been a problem. I have never had any health related issues from weed and I'm in my 40s. The only health issue I've ever had was needing back surgery, but that had nothing to do with weed.
I know you weren't making a comparison, but weed is better than alcohol in literally every conceivable way possible.