Check the casino's tabs and pages and see if they're showing how much they've got in their bankroll. Some casinos and dice sites do this and if you're not satisfied with the current one that doesn't show it to you then leave them. They don't have the obligation to show how much they've got especially the reputable ones because we know how huge they are. I think it's not a matter to me as long as I know where I am gambling and I have an idea about the track record of the casino. Btw, this topic should be on Gambling Discussion.
I believe their bankroll amount should be more privatized, instead of letting it show to the public. And if we are seeing that in public, I dont see it as reliable either as it could be somewhat an estimation. And if the casinos are reputable enough, then theres no reason to prove it more to the public. These casinos will always be standing strong as long as gamblers will continue to trust them and put their money on these casinos.
besides, it depends on the casino if they will disclose their bankroll to the public or not. some are showing what they have in vault to increase the confidence of the players. because if they see good amount of money, they are relatively at peace that they will get their withdrawal. however, for some new casinos that i've seen here, some users are requesting about their bankroll especially if they are claiming that they can afford tp offer huge amount of winnings.