Do I? Where do I start? The possible contingencies of real life in any nation or society are numerous.
The main question isn't how are people affected by their culture in their initial, juvenile belief development, but rather what and how did their beliefs form and change over time, from birth until death, taking in the entirety of an individuals life experiences and encounters.
On top of this, if we adapt the
Reformer's Dilemma from its contention with Cultural Relativism's moral argument and apply it to the issue of cultural influence and religious development, I think we can see that there isn't a whole lot--other than fear--than prevents people from wanting to introduce 'better' ideas in any society, even the one they live in.
Additionally, we could also take Muslims as a case. Muslims have the 'Negative Gospel' loaded into their Qu'ran. They know what Christians believe because it is stated in the Qu'ran; however, the Qu'ran explicitly denies Jesus' divinity, that He died on the cross, and that He was one person of a Trinity. It is possible that a Muslim, in the course of a lifetime, to eventually consider that maybe the Qu'ran got Jesus wrong.
I'm just saying.