You don't use interest or borrowed money for gambling instead you use your personal income, ...
Let’s say you have a steady income, but you’re struggling to raise a bigger bankroll for gambling. So you decide to borrow money to try your luck, nothing risky on your end, since you know you can repay the loan over the long term.
The only real issue is the uncertainty, whether or not you’ll actually succeed in sports betting using that borrowed money as your bankroll.
That’s where the risk really lies.