I’m not going with the idea of “gamble with what you can afford” because if you were able to even conjure the idea of borrowing money to gamble it means you don’t want to abide by that rule and you most likely know about it. In situations like this I think the person involved would be considering gambling as a business just as what FEDex story - if they are ready to take the risk and they know that they’ll be able to handle what comes next then I don’t see why they shouldn’t gamble with borrowed funds as long as they know that they are going for a very risky business.

But for a casual gambler, I won’t ever advice them to take a loan to gamble - if they don’t have money then let them take a break from gambling until they are financially fit to handle the loses.