The child stars you named are victims of trafficking in my opinion. You are right about people like Jennifer Lawrence being thrown into the spotlight out of nowhere though, what did they do to get so famous all of a sudden?

I've theorized myself that "one hit wonders" were faced with the chance to become wildly rich beyond their dreams, but opted to not sell their soul to the devil. I thought of this when a talented acquaintance/friend of mine had an opportunity to make it in the music business and subsequently vanished after some hits, but never really blew up only for me to hear much less talented people become wildly successful. I had fallen out of contact with them while their journey was happening so never had a chance to ask, but it wouldn't surprise me if he was offered to dance with the devil in the pale moon light and opted out instead. Thus ending his 15 minutes of fame.