[x0x0]

And in the meantime, their child (like my niece) might have clicked her way through $300+ of scummy iap that my sister didn't realize was hooked up to her credit card. People who facilitate kids spending money without their parents permission are not good people, even though the parents have the duty to supervise children. To take this to it's logical conclusion, it's the same reason that -- though parents are legally required to supervise kids -- we also put fences around attractive nuisances like pools, and throw pool owners in prison if they don't.

[qbrass]

Pools don't come with fences.

In your own analogy, your sister would be the one who bought the dangerous device and left her kid unsupervised with it.

[TeMPOraL]

Device that is not dangerous by itself and wasn't dangerous at all until recently - the danger is created by people who want to monetize kids. There's malicious intent there.

A better analogy would be a kid getting mugged on it's way to school. Should we blame parents and parents only for leaving the kid unsupervised? Should we let the robber go because "it's parents responsibility to protect their child from danger"?