Parents are stewards of their children, not their owners. Children don't have any fewer rights than adults; it's just that their parents have been entrusted to exercise those rights on the child's behalf while the child is too young to exercise them competently for themselves. This stewardship is predicated on the idea that the parent has the child's best interests at heart.
Saying that children's rights are the same as that of adults simply isn't true, regardless whether one euphemistically likes to call the parent a steward or bluntly the owner of a child.
Children have rights on a legal level, but these rights are not the same as that of adults.
Where I live, children can't vote, can't buy tobacco products or booze, nor can their parent do it on their behalf.
This goes also for the things that aren't determined on a legal level, such as parents forbidding their children to cross a high-traffic road on their own, to step inside a stranger's car, or to watch violent or erotic movies.
There can be a range of valid parenting approaches. For instance, it's not like there's only one choice about what to feed your child that's "proper parenting" and all other choices are wrong.
Sure, but different people belonging to the same religion don't all raise their children the exact same way, and aren't inherently incapable of learning from mistakes. You make it sound as if they are all so much different from you or me.
It's not just a matter of "not seeing the usefulness of it"; it's that there's an inherent hypocrisy in a parent imposing their religion on their child.
The whole idea of religious freedom is rooted in the idea that people should be free to follow the dictates of their beliefs and conscience. It's incoherent and absurd to say that granting this right and freedom generally could ever justify a parent trying to rob their child of the very same right and freedom.
This is very much a "your right to swing your fists ends at the tip of someone else's nose" issue.
Just because someone has been raised as a Muslim, doesn't necessarily mean their parents deny them the freedom to become something else.
I personally don't think in the spectrum of religious vs non-religious much, because I see when people do that, even the "non-religious" mindset can develop a group identity with common ways of thinking that are very similar, if not identical to what could be called indoctrination imo. It seems to me that because such people consider themselves free from the yokes of religion, they tend to be unaware of their own biases and tendencies to impose their values upon others, just like "religious" people do.
That's the point I was trying to make in my initial post.