Do you mean that the people who bet big on bc.game's house edge games are people sponsored by the casino?
Nah! This is not true. There are a lot of people who stake a high amount and yet are not sponsored.
If you`re active on scam accusation board, you should have seen some users come to the forum and complain about some casinos that they are making use of, and in their thread, you`ll see them stating some insane amount that they have in their account or how much they staked that led to their account being blocked.
That's the problem there some people believe that people placed large bet is sponsored but they don't realize that if scenario like that exist do they think a casino would able to survive? They should consider a lot of expenses needed to pay. And if they see a lot of people placing a large bet that means the casino they are playing is a successful one since they manage to get those whales and make them gamble on their casino.
We see a lot of it and we can see those casino representative of this forum verify their bets that's why we cannot say that they are don't exist since gambling market is so wide and there's a lot of people could able to see their advertisement especially if the casino is active dropping some nice promotion since for sure they can attract those whales seeking some fun.