I wouldn't need to use it for gambling directly. I could use it to rebalance funds between wallets that I use for gambling, without paying 2% for a mixer.
Most custodial service such as CoinBase set high transaction fees when you withdraw Bitcoin from their services to ensure the transaction confirmed quickly.
You could use CoinJoin feature provided by Wasabi Wallet if you're concered about fees, while preserve your privacy altogether.
This is not true. Coinbase's miner fees are often too low to get a quick confirmation. 2% is orders of magnitude higher than miner fees tho unless you're buying coffee. I could afford it, but 2% feels like overpaying. If I use Wasabi coinjoin I get directly linked to one particular rando who might have dirty coins, which is not as good as getting clean coins from coinbase.