But the child is already there

Its tactics like this which make it hard to see in the long-run whether one is providing relief or an incentive to mistreat a child.

I know your point, but the alternative is not different.

If you give her something, she will be mistreated because it pays.

If you don't, she will be mistreated because she didn't bring anything.

On the balance, it is better to be mistreated with a fuller stomach, even if the superior alternative would be not to be mistreated whatever the stomach status.

Of course, this doesn't say much about possible alternatives or about specifics of the sitch: like Strider said, give her something once you're already in the car; or give her food directly instead of money. Obviously, only j_k really knows the sitch as it was and as the generalities of his place are. What kba offered, to take her in, could lead to him having to outright buy her, or to the family calling the cops for kidnapping (and extorting you so they drop the charge) though of course it could lead to nothing other than a nice evening, and here is why j_k's local knowledge matters to know which is the likelier.

But of course, as we all know, it's better that kids get crippled or blinded than, gasp!, prostituted.

Anyway, my point was that though a begging lifestyle tends to be detrimental to lg's because of structural perverse incentives, as you say, once caught there the chances for harm will be there whether or not you contribute financially. It's no longer an either-or.

(But again, local circumstances vary and are what really decides it)