Or worse, it rewards those that are "in demand" elsewhere, and harms those that due to some factors outside of their control (sexism, racism) would receive less

Or worse, it rewards those that are "in demand" elsewhere, and harms those that due to some factors outside of their control (sexism, racism) would receive less interest elsewhere, so they can be paid less to keep them here. I once spoke with someone who acknowledged this, but said it wasn't a bad thing - if the market has decided that someone is worth less, why should he pay them more than he has to?