No, I dont think it is ok to "abuse" the baby swap. But what I do think, is some people are quick to jump in with the "abuse of the system" card, a little to much.
I know about the baby swap, having been there many times. Most people I know in real life, have no idea this service is even offered. Disney does not advertise it as well as say, fast pass. So believe it or not, a lot of people dont know about it.
I just find it hard to believe that the baby swap is "being abused". Sure some may lie about it. But I dont think the vast majority are.
And the OP stated they wanted to baby swap with a child on HM. They did not try to cheat the system. They did not lie. And people pipe up with the are glad Disney is not letting people abuse the system. How is what the OP asked an abuse of the system?
As another poster said, HM IS listed as a baby swap ride. HM can be very scary & intense for younger children. Letting people baby swap here, is not an abuse. It is just common sense.
And an easy way for Disney to cut out the abuse, if there is any of it, is just require parents to show the child to the CM. End of the "abuse".