Huge mistake to do this. You don't control the fee the first book will use when sending.
Betus for example uses a small fee. Your transaction might not confirm for weeks. Or, your payout might be stalled if they decide to KYC etc. If you're taking a bonus that expires relatively soon, you'll have shot yourself in the foot.
To send BTC right now highest priority is only $4.
And if you are indeed that averse to fees and want to turn the funds over quickly, use LTC.
I'm constantly educating you guys like jjgold used to do on sex and rugs.