It's stupid though, how easy is it to be 'associated' with a gang? Imagine one day a friend of yours decided to 'hold something', for another friend of his. All three of you were out for a drink or a party. It turns out that one was holding drugs, and the police catch him. All three of you become a part of a gang of drug dealers. (They don't have much to prove, since these laws would mean the state had less of a responsibility to 'prove' you affiliated with them.)
Even if one of your friends was a 'heavy drug abuser', and you never knew, you might be caught up. It's stupid really. (I don't have this problem but others might. )