Well, when incubators were a new thing, they were used to make money as a side-show. the 99% Invisible podcast did an ep on this:

https://99percentinvisible.org/episode/the-infantorium/

Thank goodness we've conquered the cruel gluttony of capitalism and no one will ever exploit the helpless to make a buck again. /s

I think another show that I listen to also did an ep more recently, but I couldn't find it when searching. I might have conflated them.