Rehab for weed? Insane thinking.
Rehabs are for drug addicts that need to gain a foundation to live in society without drugs and or alcohol as your crutch.
I went to a rehab right from 5 months in jail because I was a full on drug addict and the rehab helped me gain the footing I have under me now.

It is almost 7 years and I still do not do drugs but, I would never think of rehab for weed. I smoked weed in the rehab for being a drug addict.
Weed has kept me from being an addicted to narcotics type of addict for a long time.