It is true, only rich people do big bet, because they have no problem with money and if they win a big jackpot than too good for them. But on the other side, poor people who don't want do it. Definitely they never want to take big risk, and if they lose so how they pay it. In this way, majority of the gamblers don't take a risk and they don't think to get rich from gambling.
i even think that those people who bet huge amount are poor people who in needs money.someone who have money enough will not risking too much money , as they play for the sake of fun only , not like we are who gamble for profit then ended up losing huge amount because they have no control and limit when gamble.
People who gamble a lot of money probably made it off other things and are using it to gamble.
Some made it gambling, but most did not
If they keep gambling with it it's only a matter of time when they'll lose
When gambling you must know when to step off and when to keep playing
A thing most gamblers fail on
get a job and do hardwork for having reasonable journey become rich.