Looks like those 95masks need to be worn by the cleaning crew or they could get high from second hand smoke.Yeah, more like performance reducing. What it does is help deal with pain or mental stress during times when you aren't playing, which the mental stress part is perfectly understandable from a mental health standpoint. Many were there for months and had to leave their families for that entire time.
Also, medical marijuana is legal in Florida and as has been stated, the NBA doesn't test for weed. I believe the NFL is the only popular sport to test for marijuana usage still.