But, what happens when gamblers start winning ? The Site Profit will show in -ve and investors will be discouraged !!! It can be kept in a logic I guess...
When Gamblers are winning => Bet Profit
When Gamblers are losing => Site Profit
Investors know they're probably going to win in the end. Some even think that the site having a negative profit is good, because "the law of averages" means it'll win a lot soon.
Gamblers know they're going to lose in the end, but don't like to be reminded of it.