Could be because they have history deposit with Bank Transfer.
TBH, I'm testing my local bank transafer in Stake by QRIS. Like QR payment on Stake from my Bank, just don't like the speed credited cause take some times.
There is bank transfer deposit feature on Stake? Could you screenshot it for me where it is. I tried searching it on mine and what I found is only the deposit through crypto address or straight from using a crypto wallet.
Also if it's ok to ask, may I know where are you residing? Does the bank in your country allow the deposit of money on gambling sites then vice versa, withdraw it to receive in your bank.