Yes and no.
On the one hand, you have children who did such a beautiful job acting and then had to return to the very slums the movie centered on. They continue to live in poverty; one boy recently became totally homeless when the ramshackle dwelling he and his family stayed in was bulldozed.
On the other hand, you have children who have had a once in a lifetime opportunity which most of these poor children would never have received. The reason they aren't receiving payment NOW is not to punish the children but to protect them. For many child stars even in Hollywood, their parents ate the estate before the child came of age. The producers in this case were trying to avoid that by making the money available only in a protected trust when the child reaches adulthood.
I don't think there is a right answer here. It's a complicated situation, but my understanding, the producer (I believe) has stepped in, in the case where the boy is now homeless. I tend toward alleviating the poverty now by freeing up their pay.
It was an excellent movie, by the way. I do recommend it.