For father, I can say that he can gamble out his money according to his wish as he knows what he is doing due to his experience. Also, that particular money belongs to him, so we can't impose any restrictions upon him for spending his own money, but as far as they're concerned, teaching the value of money to the children is significant. Also, as per Nevada's state laws, he was underage and legally isn't allowed to drink and gamble, so he was not supposed to do that; the responsibility lies with the parents to prevent him from performing any illegal activity.
Parents should be blame the way children handle money. Any child that spends money with no control, I believe the parents allow such freedom to be so. A child who has a good up bringing will never spend money in a wasteful manner.
We have seen many cases where a child is allowed to spend money his father gave him without any lessons on how to save his money or use their money for their own good. And his parents always pampered and obeyed their children's wishes. This makes their children arrogant and wants all desires to be achieved immediately, even though it is not necessarily good for them. We certainly don't want to see our children trapped in gambling without a way out, so we must monitor their association well and not just let it go.