I will throw in a reason why they don't... FEAR. Fear they will be targeted by these demented terrorists.
Now... it is up to the leadership in the Muslim community to come out and start this. Sitting by and watching a faction of idiots terrorize society because they have issues with it is no excuse not to come out and condemn it publicly and consistently. NO excuse. Instead we have the fools at CAIR as the face of Muslims in America. That is unacceptable.