I'm really glad you got her back. Are you sure they were actually "nabbing" her though?
I have found 3-4 dogs roaming the streets before and always took them into my home temporarily while I look for a collar and ID or decide whether to drop the dog off at the animal shelter (so its owners could find it). The little girl probably told them you were outside so they put the dog back out. They probably didn't mean any harm.
That would scare the daylights out of me if my dog ran off like that. I would be afraid she'd be attacked or hit by a car.