It a horrible fact of life that homeless people in general are poor and ugly. Due to a complete lack of physical and mental health care, some of them are down-right scary. It makes it impossible to trot them out in front of the cameras to make everyone say "AWWWWW, poor widdle baby doesn't have a thing in the world. Gub'ner Mommy really cares about us, cause she's helping the baaayyyybeeeess."
People as a whole are stupid and easily manipulated (I mean, come on...the Simpson girls are huge stars for chrissakes, and as far as I can tell their only skills involve...umm...well...having nice hair?). All they see are the big cheeks, whispy hair, gloopy eyes and helpless loling and that turns off the logic switch. They don't seem to realize that a BABY contributes NOTHING to society, whereas a single adult, given the proper resources and assistance, can get themselves to a place where they're not only self sufficent, but actually contributing additional resources. Imagine that.