In many countries you have a special office that handles company vs client issues, like when they don't respect warranty and such. You can always try that.
If you're looking for something like the SEC for stocks, I'm not aware of anything like that in my country that deals with gambling.
I was thinking that if a gambling commission can issue licence to such gambling sites, they may have read through and agreed on the basics of T & C so why can't the same commission stand in that justifiable position in this case? Or it's assumed that they're working hand in hand all for profit gains and not respecting the rights of the gamblers.
How are you going to go to courts and say "this casino scammed me" when it is illegal for you to have any money in any casino? That is why it's clear that some places are just not caring about you at all. Plus, there are some casinos who are established at shady places, meaning that they do not care if they steal your money or not.