I don't doubt that it's possible to win a lot with gambling; I just don't think it's very common. Here in Brazil, I've seen many people win the lottery, but I prefer to be cautious and not get carried away by these stories. This guy was very lucky.
Getting people to get carried away by their feelings is actually one of the oldest and most effective marketing and advertising strategies used within the gambling industry, specially lotteries.
Why do you think lotteries are so eager to make a show on the luck of their winners?
That is done with the intention to encourage as many people as possible to try to emulate the lucky success of those lottery winners.
I have even seen lotteries which pay for an special event and party, in which winners are giver their money in front of hundreds of people. They do that because it is profitable for them to get more people to play.
It is similar on casinos and bookies.
I would not be surprised if the case of this specific guy on facebooks started to be advertised by the casino itself, in order to invite people to join their website.