Gambling is good if you are that lucky to win most of the time but generally it's wrong when you're more of losing than gaining something from it....
Its way more complex than that, gambling is providing economic growth and entertainment. Look at all the jobs its creating and how many new games are getting developed.
Okay, gambling is a business that provides that what you mentioned but how many are benefiting from it (like the owners, workers, game developers, smart and lucky gamblers) compared to the people who are losing from it. There's not once I heard a story about gambler who got rich, it's always a gambler who lost his fortunes because of gambling. They're most likely to be addicted, winning at first getting excited and trying it again hoping to win more, then they lose more than what they actually gained, then they try it again hoping to get back what they've lost at the end up losing everything. Yeah, just a usual story of a gambler...

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