What's your definition of successful? I know people that use weed everyday who make over 100k/year, have their houses paid off, have good relationships with their families. Don't get me wrong, I've met a lot of loser potheads, but to say they're all unproductive, lazy entitled losers just reveals a limited perspective or prejudice.
I also know people who drink three beers every night who aren't deadbeat alcoholics; they work good jobs, take care of their families, and live good lives.
Just because you smoke pot doesn't mean you're getting stoned out of your mind every night.