Gambling is a addiction bad addiction. Few days ago I see a user lost 65BTC and another user 30BTC amd another user 12BTC in a dice site. All those user lost huge huge within 24 hours.
But even if we say that it is a bad addiction, a lot of people are still gambling despite the fact that it will really bring you down to the pit. Regret and depression is one of the most popular effect of gambling to people.
Also, these gambler might be rich so they have nothing to worry about those losses. We don't know what they are thinking losing that great amount to the site but all we know is that they had lost and it is hard to get that back.
Because people are usually rich from gambling, in the end the wealth will also run out in gambling, which is why they continue to gamble despite losing a large amount. Unlike the case if you are only looking for targets in gambling, if you are able to control emotions then after you reach the target you will stop, but if your emotions increase and cannot be controlled then you will become a gambling addict too.
Who's familiar here in STEPHEN HAWKING, I remember that article state about human greediness. He says that Humans Are Still Greedy, Stupid and the Biggest Threat to Earth. Just like gambling, there are no limitations to their emotion even though they have reached their targets profit they still continue in gambling. And a high possibility of lose when you more chasing in money of gambling, when you are in addiction it is hard for you to control your self and don't let happen this thing.