Not addicted that they will get withdrawal simptoms, but that people are in such companies that cannot live a day without weed, and spend most of their money on it. And the thing is such people mostly spend their time with one company for a long time and it makes it harder to quit for them, since after 3-4 years they don't have a lot of non smoking friends left or their mind is a bit messed up so they just keep on smoking, some get out of this habit, but there are people who stay in it for a long period of time. That is what I call addicted.
And people change when they smoke for a consistently long time. They become more stupid (don't know how else to describe it).
Constant usage of weed is for people who want top run away from problems.