Unfortunately, you can't expect others to do for you what you did for them. The reward for this man's generosity was ingratitude and contempt from the others at the casino. It would have been better to have helped someone who was homeless and hungry; it would have been more worthwhile.
I agree with you. This is my opinion, too.
Yes, helping a poor, homeless, or hungry person is much better than honoring those ungrateful people who sit in casinos and spend their money on gambling, girls, or other worthless things.
In any case, I expect this generous man has learned a hard lesson. I guess the next time he wins a generous sum, he'll help the poor or donate it to a charity instead of spending it on these damned, ungrateful people.