The comparison with Rioli is pointless. Personally. I find the whole Rioli thing tragic, and while faking a urine test is a "bad thing", he only did it to hide smoking a bit of weed which is not performance enhancing and should not be illegal in the first place (isn't anyway in SA and the ACT). So I would be totally in favour of lenience towards Rioli. I'm willing to forgive him his bad choices (like not playing for Richmond as a Rioli should).
Weed in small doses is performance enhancing as far as calming anxiety and nerves before a game.