An injustice that comes to the fore is the literal abuse of the women who are giving their eggs. Say what you want about egg donation, but the woman's body undergoes a lot of stress (albeit self-induced) while the companies provide no follow up health care.
For what it's worth, I think the entire process is wrong. But, if a company has the desire to purchase the eggs from a woman, they ought to make sure she has adequate care afterwards. A woman's value is not relegated to her eggs. She is made in the image of God (c.f. Genesis 1:26f).