Indonesia is the country with the largest Muslim population in the world, and in fact gambling does not recognize religion... some Muslims who are not devout mostly gamble since they were teenagers. that means, religion is not a barrier enough to sort out between gambling interests and not...
A serious problem in Indonesia today is, gamblers are too addicted to returning their lost money when playing slots, even though slots themselves are games that are already known to win... so I think the perfect factor to be used as a reason why many people gamble is economic factors, not religious factors...
Whether gambling is prohibited or not, as long as their economy still hopes for money from gambling, then gambling will continue to live there.