SUI blockchain doesn't charge any gas fees on stable coins, it is the fastest and most reliable.
Depends on the platform you're using.
SUI blockchain is not that popular compare to other chains and many platforms have not yet included it in their deposit and withdraw options. The last time I used the chain was when I participated in airdrop and the project team forced the participants to use the chain to receive their reward.
Is a casino platform we are talking about so actually even if there is a chain that doesn't charge fees but in the casino with fees for withdrawal will definitely do the same thing on the coin if it was among the coins they have for withdrawal and deposit, we could check Spinly, they have fees to all the ones they have if you are withdrawing, although I can't say that I have make withdrawal through all the coins they have but however I think there is no one they charge below 1 dollar, so the same thing would have also been charge on SUI blockchain if they had it.
I have made withdrawal through the platform and that network isn’t listed on the spinly website and there is no way someone would have to make withdrawal from that network or chain since they do not listed over there, currently if you are making withdrawal from usdt Trc20 they charges nothing, I have withdrawn usdt in several network such as Erc20, Trc20, TON usdt and Sol usdt all these are free, they do not charge anything from their site. However, I believe that anyone who is gambling with bitcoin could be charged for withdrawal.