This topic has been discussed so many times on this board. However such stories will not end because people will always go the extra mile to satisfy their uncontrollable urge. I think your friend is suffering from gambling addiction. He need to reconsider his gambling activities, take a break or seek professional help. Anyone who goes to the extent of borrowing with interest because of gambling is not a responsible gambler.
You're right, topics like this are nothing unusual because several topics were made before about this already and everyone has the same answer that it's always been very risky to take a loan when you are about to gamble. Too many problems will be caused by it and made by that mistake. If someone goes to that point of borrowing, we know that they're not responsible and you're right. They have the guts to spend other people's money just to gamble and will plead that they're going to use the money for better cause but the reality isn't that. They're going to use the money for them to keep on gambling and that's the reason why many are being put into debt due to that bad action.