The Catholic Church actually asserts the "primacy of conscience," which says that each Catholic should get all the information, especially considering and valuing the Church's doctrine, and then make their own prayerful decision.

Unfortunately, even most Catholics don't know about this, since it's not in the Church's interest to have its members off making their own (informed) decisions. So most Catholics who hold differing opinions based on their own research, consideration, and prayerful process just figure they're "bad" Catholics.