I'm failing to reconcile the image of a hypothetical teenager who is both so irresponsible and incompetent that you can't trust them to get up or make breakfast on their own without burning down the house while simultaneously being capable of having an after school job.

If you can't leave them unsupervised in the mornings, surely they can't be left alone after school either. Net net, there's going to be some time they're unsupervised. May as well let them get some rest. Maybe the lack of sleep deprivation will even encourage better decision-making.