Why would they send their money to Binance when they know its a centralized exchange and can give away their details easily if a legal case is against them.
If freebitco.in has decided to steal their users' funds then they would have figured out a way on how to launder the money and so they won't leave a trail behind.
The best thing here to do would be those people who have high amount on the site file a legal complaint against freebitco.in and only then the authorities might consider taking an action against them.
Binance is famous for its shady practices. Binane has been helping Chinese citizens to bypass KYC verification. Maybe Freebitco paid enough, maybe Freebitco withdraws it on an account that's KYC verified by an absolutely different person, who got a share of some money in exchange of submitting KYC documents (too many people don't care about their privacy and KYC documents if you give them a few bucks and that's a very sad situation, it shouldn't be like that).
Btw who is in charge of FUN tokens being traded on Binance? I mean, who gave Binance FUN tokens in the wallet? I don't know how it works but I believe that Freebitco isn't just trading on one person's account, it should probably be more official.