Where is the crack addicted mother in this story??

It was a hypothetical.

If someone wants to donate or give, then they need to understand what they’re doing - transferring ownership of said donation /gift to someone else.

Yes, and that "someone else" is the child, not the kid's parent.

And that afterwards, that person is free to do whatever they want with said gift or donation, because it now belongs to them, and not the giver.

Yes, that person being the child in question, not the child's parent.

Also, parents are allowed to take things away from their children. That is their right as the child’s parent.

If you don't want your kid to have those presents, then why ask for them? Oh right, so you can use your parental "right" to return them for cigarettes. Asking for donations under false pretences is trashy as hell and you're a fucking skank for defending it.