Well 1) everyone does not have equal access in practice and 2) they should have to pay more specifically to help provide more equal opportunities to everyone in

Well 1) everyone does not have equal access in practice and 2) they should have to pay more specifically to help provide more equal opportunities to everyone in the future instead of resigning ourselves to dynastic feudalism. And also because ultimately that is the explicit agreement that one enters into by choosing to participate in this society.