after reading the thread subject and replies one thing is confirm that playing in casinos and dice game is fully risky because owner of the site can do anything with our account and what ever we won can go anywhere then it is totally literally waste of time, damn i also wasted so much time and my bitcoins, now i will stop fully.
thanks guys for giving so good information.
Yes, the owner can run with everyone's money if he wants.
But will he? Big sites like Prime Dice and others earn a good amount of BTC by day, so would not take much time until they earn honestly what they could steal. Plus they would really piss people off, they would DOX them and go after the owner, and they would have problems with the law too. It surely would hurt them in real life.
I think it is unlikely that the owners of the big casinos will just run away or cheat people, even if they are dishonest, because it would not be profitable