Charging the perpetrators after the fact is certainly important and you're right, it's not done enough. This is precisely because society is allowed to be influenced by the advocates, who not only tell people they should do these things but tell other people (including those who enforce the law) that they should condone and support such actions.

Charging the perpetrators of crimes doesn't stop the crimes. Plenty of crimes are dealt with by the justice system and they still go on being committed. Silencing those who advocate, say, the objectification and subjugation of women might (I say might) actually prevent some incidents of rape, *and* might also lead to rape being prosecuted more diligently in the courts. Somebody or bodies told that swimming champion whose name I've forgotten that it was okay to rape a young woman, and the same somebody or bodies told the courts to go easy on him. Punishing the somebody or bodies, or at least silencing them, might have prevented both outcomes.