"Cnsidering how popular it has become for people to murder their their children when they are unborn or partially born merely because they represent an inconvenience, I'm surprised that such tales of 'inconvenient' children being dealt with in a similar fashion are not far more common."
There's also the more likely explanation -- there are a lot of stupid people out there.
Agreed, although it takes a particularly depraved brand of stupidity and malice to do something like this.