Reality is, probably 60% of NFLers smoke. Despite the rhetoric, testing is really light and easy to beat. But if you get caught once, you start getting tested on the regular so you pop a lot. I get that he should shape up and not use when he's on the radar, but it's pretty absurd that pot use carries such a heavy penalty.
You can claim he has character flaws or addiction or mental illness because he can't stop, but regardless of his reason, his use of a relatively harmless drug should not be costing him millions. Period, full stop.