If women engaged in surrogacy for altruistic reasons, then surrogates would come from all socio-economic backgrounds. But they don't. What a shock!
Getting a woman pregnant on purpose, knowing before conception that the baby will be removed from its birth mother, is supremely selfish of those who want the child. They are knowingly traumatizing the baby. The intentionality of the pregnancy differentiates it from adoption.
Being able to buy access to women's bodies also totally reinforces the idea that it's ok for men to buy sex from women, and that it's ok for people to sell organs. If one bit of the body is for sale, then why shouldn't the rest be?
In the instances when the child has a disability, and the birth mother cant bring herself to abort, but the surrogate couple no longer want the child - what happens then?
If the surrogate dies in childbirth or is left disabled - what happens to any kids that she already has? Who Will look after them and support them?
Infertility is totally heartbreaking, I get that, but that doesn't mean that another woman's body should be treated as a consumer good, so that an infertile person can have a child. Sometimes, we just have to accept that we can't have children, heartbreaking as that is.