That's one thing people need to keep in mind: if used in moderation, it's fine. If used in excess, it has the potential to become a problem.
Most of us have been drunk. That's a good example of misusing alcohol. Having a few beers to get a nice relaxing buzz would be reasonable use.
Marijuana doesn't make you stupid. You make you stupid. Do you have the self control to use in moderation, or not? It's actually the least addictive when compared to alcohol and cigarettes. It COULD become psychologically addictive, but like someone else said, so can other things like video games.
If someone knows a person who "became stupid", chances are that person was doomed to begin with. Almost everyone I personally know who smokes it is smart, has a career, a family, and is on the right path in life. I can only recall exactly TWO people I've ever known that were bums who did nothing with their life, and I know for a fact that they were like that before they got into weed.
If you get drunk every day, will you not end up equally, if not more, stupid?
As for cost... hah. $10 for a dimebag vs. $10-15 on a 12 pack. Personally, it takes me 6 beers to even catch a nice buzz. That sucks. A dimebag.. shit, that'd last me 3 weeks. That and people have no problems whatsoever with going to McDonald's a few times a week and dropping $4 on a super-sized meal chock full of salt and grease - as if that's good for you.
The only extreme side effect it has going for it is smoke in the lungs, but that's what water bongs are for
People need to be a bit more open minded