Why are you so concerned with seemingly minor jokes about Jews and Jewish-ness?
I'm glad you said seemingly. Jokes do seem minor, but what they betray of the human heart is not minor. And what they can cause in another human heart is not minor.
Coming from the biblical perspective we see that the Jewish people hold a place in God's ultimate economy that is unique. In Romans 9-11 especially Paul is vigilant to say to Gentiles (that is, everyone who is not a Jew), "Beware of belittling or putting down the Jewish people. Don't say, for example, 'The branches were broken off so that I might be grafted in'--that is, 'Jewish people have been rejected by the Messiah so these Gentiles could be included in the Messiah.' That's true," Paul says, "but you stand fast only through faith. Therefore fear, lest pride arise in your heart and you exalt yourself over another ethnic group, especially the Jewish people." Then he says, "Those branches are going to be grafted back in again."
God has a future plan for Israel. They—together with us—will be members of the body of Christ: every Jew who receives and believes in Jesus along with every Gentile who receives and believes in Jesus.
There are two ways to approach this issue of ethnic pride and ethnocentrism. One is to focus on the unique place of the Jews and say, "Get it out of your heart and mind to belittle the Jewish people." The other way is to acknowledge that every ethnic group is created by God and ought to be treated with respect.
We who have discovered our own sin and the tremendous mercy of Jesus at the cross should be the slowest of all people to use racial slurs or ethnic jokes. Such jokes involve not only putting others down but also putting ourselves up, which is exactly the opposite of what the cross should do in our lives. We should go down and others should be lifted up.