Children in these care homes are extremely vulnerable to this type of predatory behaviour. Some (maybe most) have already been abused by family members.
This is not unique to Thailand. I am from the UK and, if I mention Cyril Smith (former UK Member of Parliament and disgusting pedo) other Brits will certainly recognise the similarities. A massive cover-up of kids in care homes being sexually abused with the full knowledge of those people whose job it was to protect them.
I'm sure that there are examples in all countries.
IMO there needs to be much closer supervision of these care homes, and extreme punishments for anyone in a position of trust who is found guilty of abuse, or enabling abuse of children. Life sentences without parole.