You are referring to the fact that the couple was reportedly responding to a "Rick Sanchez" (as I will now refer to a person stupidly making anti-semitic remarks).
Yes, it is sad, but there will always be stupid people who say wrong things. As bad as that is, I still stand by the idea that it isn't illegal to be stupid and we do still have free speech in this country. Even if people say intolerable things it does not give anyone the right to react to them abusively.
One stupid does not justify another.