[nailer]

You're right, it's not a justification. The reason I think we do all those things is because it's good for society: there might be talented kids that have poor parents, so giving them a good start in life creates more successful adults. More successful adults is good for the economy and for the harmoniousness of society.

[Jabanga]

We could provide people with the market means to provide student loans to the parents of promising children. Then the market will take care of it, without any compulsion, and far more effectively than a nondiscriminating blanket redistribution based solely on reported income levels.

I personally think that guaranteeing equality of opportunity will have more negative social effects than positive, by reducing incentive to produce resources in order to provide for one's own children, since one can instead be poor and let the state force other people to pay for their upbringing.