I think there is probably a higher proportion of religious Jews than of religious Christians, given that many Christian states are secularising and de-emphasising or disestablishing religion (even in Britain, which is nominally a Christian state with an official church, church attendance is at rock bottom). It is a minority world religion but it gave rise to Christianity, one of the widest spread world religions. As someone going out with a religious Jew, I also find that idea slightly offensive and would point out that you need to do your homework on religion, belief and understanding the longevity of Judaism as a world religion as opposed to e.g. Zoroastrianism or Mithraism etc.
Let's see here. Non-practicing Christians ... well, except some Catholics, they usually don't consider themself Christian. Most who self-identify as Christian are practicing, because it's not generally considered an ethnicity as well, like being Jewish is. And even if there were only 10% of self-identified Christians practicing, they would outnumber practicing Jews 30 to 1 or so.
Longevity compared to Zoroastrianism? Hmmm ... well lets see ... Zoroastrianism is still around, and dates from nearly as far back as Judaism. It just has even fewer followers, and that's the only reason it's not really considered a world religion today (250k followers, I think, it is to Judaism what Judaism is to other major world religions).
I did make mention that Judaism did indeed have a huge impact in that it was the root of all the Abrahamic religions. And I further stated that for that reason, Judaism ought to have a place in the game and I agreed with its inclusion as a religion, as a compromise - since including it as a civ in the base game seems a little much (then we'll have to include the Canadians and the Welsh and Scots and every other tiny group - I am all of these things, but not so stubbornly vain to think we need inclusion).
Scotland, actually, is a relatively good case example of why Judaism is a good compromise for inclusion and why Israel just doesn't merit being included as a civ. Scotland is just as old, in fact, has been in continuous existance far longer. It has been under foreign domination for far less of its existance (only since 1707; heck, in 1603, it was a Scottish king on the English throne!). It has produced many great thinkers and scientists (Alexander Graham Bell, Adam Smith, etc). Under the British Empire, Scots formed the backbone of the British military, and practically conquered the world. Scotland even has a sort of diaspora, with nearly 30 million Scots outside the borders (five times as many as the Jewish diaspora). But, it is nonetheless a minor power, and Scots and people of Scottish descent are not so vain as to demand otherwise. You just don't see that many Scots clamouring for the inclusion of Scotland.
It's not the people who don't want Israel included that are being political, I think ... quite the opposite ... you just don't hear this kind of fuss about including other bit players like Scotland. Let alone people making paranoid accusations about political supporters of Stalin and Mao being everywhere! Commies lurking in every shadow, foisting their agenda on popular entertainment! Oh no! It's the 1950s!
So ironic that you should make accusations about others being political, while you engage in neo-McCarthyism ...