I don't know much about those sponsored people but I think I have seen some social media guys to win huge jackpots and you may be right about those.
Do you mean that the people who bet big on bc.game's house edge games are people sponsored by the casino?
At first I never thought about it like that, but after reading your post maybe it could happen. Moreover, seeing the game crash, quite a lot of users bet more than $1000 on the game crash. that's so crazy to me, do you think it's also sponsored by the casino?