The exploitation of the Hispanic girl's story was a bit much. Trump is terrible on immigration, but that doesn't justify stuff like that.
Her story is real, and it's not unique to her. There's thousands of families in the same situation.
It would be exploitation, if we had reason to believe that Hillary has no intention of doing anything to help them, or worse, actually wanting to deport them. AFAIK, there's no evidence of that though. There's real differences between the campaigns on immigration. I don't see why it's bad to acknowledge that with actual stories from real people.