I was raised Methodist. My parents were Methodist, and we went to a Methodist church every Sunday. I knew that we were Methodists, because that is where we went, and I knew that others weren't Methodist, because they went elsewhere.
As a child, I believed that everyone worshiped their own way - hence the numerous churches. I don't know if my parents told me or if I just assumed that people made their choices and that was all right with God because he listened to us all as we were all his children, but that's what I grew up believing. I don't know that I ever thought that those whose faith differed from mine were "wrong;" I just thought their faith was different.
Perhaps that was one of the intangible benefits of growing up Methodist - that you are encouraged (or at least not discouraged) from questioning faith, or asking about how things come to be. In my experiences since I left the nest, I have encountered scores of people of different faiths. Some of them believe similarly to me, others believe that the only way to worship God is to do so "their" way (i.e. they are right and I am wrong). It's interesting to me to be a part of an adversarial conversation where I don't believe the other to be "wrong" while they believe me to be.
I don't think I'm better than those who believe differently than I. I don't think they are better for thinking I'm wrong. After all these years, the one thing I am most convinced of is that God encourages us to find our own faith, and to adopt that manner of belief that best supports them.