It is impossible to be prescient about every broken home or toxic environment. Meanwhile a leg up to one student means his next generation and his grand-generation are educated and have now transcended classes. I wouldn't advocate the same benefits to a recipients following generations (if they indeed made it to the middle class and above). The problem comes when this benefit keeps on going for generations and generations in the same family. This is the case in India right now and is a very big reason for disillusionment with the education system.