> you'd think a lot more people would be excited to adopt babies.
A couple things;
1. The primary barrier to people adopting babies is the insane expense and rigamorole involved (at least in the US). You might argue that the expense is justified, but it doesn't change the fact that it's extremely difficult and expensive. Plus, in some states, adoptive parents are given lower legal priority than the birth mother. I know a couple who had to give up a baby they adopted months earlier because the birth mother sobered up (temporarily) and decided she wanted her baby back. So not only a huge expense, but a huge emotional and financial risk as well. This is a by-product of the law, not of the difficulty of raising the child.
2. Despite this, most healthy children do get adopted. Most of the un-adopted children have physical or mental health issues that most would-be parents are not equipped to deal with.
I'm not saying that caring for a baby has no cost, but I think you argument ignores the largest challenges of adoption.