Surprised that someone is willing to give these loans. What collateral is there other than the idea that future earnings may improve? It sort of is implicit support for the idea that taller men do better.
It's sad to say but ultimately the extra few inches will make a difference in lifetime pay. Going from say, 5'8" to 5'11" is a great difference so to many it's a simple decision to do it. Short men do have a hard time in our society. Discrimination against them is so common that I don't think people can even perceive that they are doing it. Additionally, many become permanent butt of jokes which has to be hard on the ego.