Years ago I was a daily cocaine user, tried heroin a few times, etc. but letting go of those was easy for me. When I decided to stop, it was over and I haven't touched them since. With marijuana I had wanted to quit for at least a year before I succeeded. The adverse effect on my life was clear, but the ritual was completely ingrained. I eventually managed to quit by radically changing my lifestyle so that I was no longer surrounded by the culture and the drug itself.
I still definitely have cravings, especially at night, and very occasionally I need to go have a few beers as some sort of substitution therapy (even though I don't really enjoy alcohol, and never drank before quitting).
That said, I agree that the author of the article is being ridiculously presumptuous and is wrong about the mentality of most marijuana users. (Edit: I also think this guy is totally, totally full of shit and making up the entire story.)
Weed on the other hand I used in massive amounts, so I'm sure that was part of my fixation. It was ingrained into all of my daily routines (exercise, waking up, sleeping, eating, coursework, socializing), plus I began smoking during a rough period in life so maybe that's why it had such a hold on me. Thanks for the encouragement!