Beacause most people are greedy and they are always looking for easy money.
When they win they want more and keep playing but they forget that sooner or later their luck will be over.When they lose they can't accept that loss is a part of the game and continue untill they get their money back or lose everything.
there thousands reasons could explained why gambling so addictive , but the most popular are because people love their adrenaline to get pushed it's make them feel self satisfaction , make them happy. and yeah sometimes it's addicting due they feel how easy making money though gambling , you don't need to work for hours just roll the dice .When they win they want more and keep playing but they forget that sooner or later their luck will be over.When they lose they can't accept that loss is a part of the game and continue untill they get their money back or lose everything.
It's just our imagination. Gambling is presented to all of us being the easiest, safest way of earning money fast, while in reality... Yes, it's easy for the house to make money without doing anything. It's still fun for me to gamble, but no more deposits. I'm telling you something.. deposit = donation, most of the time
Maybe gambling is never meant for making money from it but it was made for entertainment. Always gamble carefully with the amount you can afford to lose. But most of the gamblers thinking that they can easily and faster way can make money gambling and end up losing all their money to these gambling houses.