From what I have read here, the underlying theory is that someone younger doesn't have kids/spouse/family/etc. So they are more willing to work long hours (I gu

From what I have read here, the underlying theory is that someone younger doesn't have kids/spouse/family/etc. So they are more willing to work long hours (I guess without pay since salaried?). Also the theory is that someone older means they would want more money for their experience. Note that I don't actually know, this seems to be the running theory as I understand it.