@MasterOfCoin dont remember mc's age, but I think it is below 10. Particularly as him going into town was already unthinkable before last chapter. And the girl is definitely not 10 yet.
No, they have food issues, so as I said before, I think they are looking to downsize. And if it doesn't happen instantly, then all the better, because the kid scavenges more food than he eats. And now adding the girl they are hoping for greater success. Either way.
And I am fairly sure they know he will end up going deeper than the outskirts, at least the orphanage staff seems to implicitly encourage him to, even collecting info for him about stuff *beyond* the outskirts, as they are more valuable.