'I struggle with the idea of branches of religion in the way you describe - a "liberal" as opposed to a "strict".'
But every religion has followers that range from liberal to strict. And that's a good thing, otherwise religions would be made up entirely of fundamentalists.
As Catholics or Protestants I guess there is some luxury in that you can say, no I'm not Catholic anymore, I'm Christian -- but what about Muslims, or Jews? If you say that you cannot be a liberal Muslim, you are effectively saying they cannot be religious at all, which is unreasonable.
You say religion is made up of rules -- but in most cases, there is not one single interpretation of those rules. Look at Judaism, where you have Orthodox, Conservative and Reform Jews. I think basically the same thing has evolved in Catholicism, it just hasn't been institutionalised in the same way.
Strict Catholics believe the pope is always right and therefore they have to follow the interpretation of the Bible as set forth by the Church. Liberal Catholics tend to believe that the Church has not modernised enough, and that on a handful of issues they can depart from Church teachings, without having to forsake their entire religion. (And Catholicism differs quite a bit from other Christian traditions.)
I agree there is a lot of religious hypocrisy around, for example George Bush talking about what a good Christian he was while bombing countries back to the stone age. But having different branches within one religion isn't hypocritical to me, I think it's natural for different interpretations to evolve over the course of centuries.
(sorry again OP, but thanks for not minding the tangent so far!
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