I believe scam investment websites have been getting increased regularly which shows that they keep on profiting by running with others money. Now gambling is getting more attention from users for which scams on gambling websites might happen.
When a gambling sites is operating profitably, they do not need to scam people as they want to have a continuous profit with their business, and nowadays people are already smarter than the past, so I guess the incident of being scammed with be lessen and more people will be coming in to gamble and have fun without being scam.