Watered Down Religion

Yesterday I was having a discussion with a friend about the fact that her church frowns upon women wearing pants. Now it is my view that is well within the rights of a church to do so, but I personally think it is unwarranted.
This however led to an interesting observation. Churches found in rural or poor areas are often what we call more "traditional", while churches in more urban/upscale locals often are more "liberal".
My friend tried to make the argument that these "liberal" churches often practice a more "watered down" religion. I, of course, disagree with this sentiment. If we use change to indicate the "water to religion quotient" of a given church, then even the most traditional of churches are rather fresh tasting.
The reality is that churches/religions are comprised of people, and these people are are influenced by more than just the church. The mores of a society will always affect the values,norms and virtues of a given denomination.
In light of this, it is evident that churches will always change and adapt. In fact, I put it to you that the faith of a believer 100 years ago is the same as the faith of a believer today. In other words we should not pay attention to frills each denomination may display. Skirts, head gear and general behaviour are all things that will change over the years. The only thing that should be measured is the devotion to the primary tenants and directives of the given faith.