You didn't spell out any reason why that's exceptional. You literally used working out as an example. At that point, any form of self-soothing is a mind altering addiction. Tapping your foot while waiting would fit that definition if exercise does.

There's nothing exceptional between being addicted to marijuana, just like fast food or gambling. It's purely habit, not the item itself. It's psychological, not physiological. Physiological addiction exists. That's why withdrawal is a thing for certain addictions and I don't just mean "aw, they're in a bad mood cause they stopped smoking weed" or "oh, they went on a diet so they're cranky."

Gambling isn't the core problem when someone is addicted to gambling. Theyre filling a void with the wrong thing. It's, again, something for emotional therapy. But it says nothing about marijuana.