I think he let the kids alive because he already know that kids would never survive in the first place. My point is lets imagine that the kids want to eat, maybe they can hunt but in the middle of hunt, they meet a pack of monster etc.
woah nice he spared the kids, well i guess he has some moral, good writing !
i predict that after this their destination village will also reject them like what they did, but this destination village is also one of hero's illusion magic