It is absolutely psychologically addictive. Physically, not so much.
The fact of the matter is that you have a substance abuse disorder once you have a clinical or functional impairment. Marijuana use in the NFL, by definition, fits this criteria as it significantly impacts their ability to work.
Let me ask you this 3rd. If you had to never drink alcohol again to maintain employment, and you couldn't or wouldn't stop, what would you call that?